A member of the Atlantae division of Yomi and disciple of Ogata Isshinsai. She is deeply in love Ryuto Asamiya, her desire to be strong is because she believes he will love her back and despite his cold attitude toward her he is shown to cares about her.
Rimi Kokorone past is not completely known, but what is known is that she challenged and defeated the leader of a group named Titian for the position of leadership. However, the other members didn't accept her as the leader and decided to get rid off her and the one who defeat her will be the leader. Rimi was tired and would have sustained perminant injury if Ryuto didn't interfere and defeated her attacker. Ryuto tell her that he she is strong and he like strong people, unknown to him he gained her affection and love. Rimi started to train so she can become stronger so that if she ever reunited with Ryuto she would be loved by him. She become part of Yomi under the teaching of Ogata who was also the master of Ryuto. Thought she was reunited with Ryuto he was crippled in a wheel chair and had a cold attitude, but even with this her affection to him didn't change.
Rimi first appeared as one of three shadowy figure in an underground facility in front of Ryuto when he was with the God Fist Akira Hongo and the Demon God Fist Silcardo Jenazad.
Later, Rimi was giving a "training lesson" which was observing the method of killing used by members of the weapon division when they were trying to stop Shinpaku Alliance from delivering a disc full of data about Yami. After the weapon user fail she was ordered to retrieve the disc and was encouraged by Ogata who lied to her by saying that Ryuto is counting on her. Rimi used her speed to to follow the Shinpaku Alliance, who split into two groups, and search them before they can notice and moved into the second group. Niijima who had the disc used hid blinding ability to blind with his surrounding after sensing her coming. Rimi searched the two remaining and become confused because after seeing that none seem to have the disc. However, a weapon user told her about Niijima and she took the disc from him.
When Miu arrived she demanded the disc to be returned and called her Yomi. After commenting on Miu speed Rimi ask how she knew she was part of Yomi and due being too frank she revealed that she is part of Ogata Yomi, she is deeply in love with Ryuto and was appointed the leader of the Titans. Niijima tell Miu to capture Rimi so they can extract all the information they can about Yami from her. However, Rimi tell Niijima that she is part of Yomi not Yami and she don't know anything about Yami much to his dismay. Rimi retreat since she fulfilled her mission in retrieving the disc, Miu chase her and Rimi sense that she is being chased by someone who possess a high quality level Ki. Miu catch up with Rimi and take back the disc. Rimi fight Miu for the disc and use her Anti-Clock Wise technique against her. Seeing this Miu comment that Rimi had a strange training which Rimi don't react well to it and tell her not to complain about Kensei (Ogata) specialization training as it strengths one strong point and she managed to get to the top of the Titans with her speed only. Rimi accelerate the speed of her attack more and more until she took back the disc along the bra of Miu.
Rimi tell Miu that Ogata told her that that she have a raw talent that is one in a thousand and she was different from the other girls only for her to notice that she is holding Miu bra. Miu then relaxed and decided to try again, which caused a strange feeling to overflow around her, something Rimi didn't felt before and her instinct told her that she wouldn't win if she fought Miu fair and square. Thus she decide to retreat, but Miu managed to follow her easily and told her that separately her movements are perfect but she still do useless move.
Rimi remember what Ryuto told her about Miu, but refused to tell her what was between them and thought that she have some kind of a relationship with Ryuto, this caused Rimi to declare that Miu is her sworn enemy and start to attack, Miu note that while her movements are not perfect it shows the quality of an incredible genius. The fight reach to a dam and Thor fall on them which caused them to let go of the disc. As the disc fall into the dam both girls uses the style of their masters to run on the dam wall to retrieve the disc and both catch it. As the two jump back up they continue to fight. However, both notice that Thor is looking st their exposed panties which embarrass them, but Rimi kick him and call insult him by calling him fat all while dropping the disc. This anger Thor who caught the disc and swear that he won't give her the disc even if her dies. Seeing this Rimi decide that she have no choice but to "undress" much to Miu shock. However, what Rimi meant by undressing was that she would take off her shoes stste that once they are of she will become wonderful.
The shoes are revealed to contain gold in them due it gravity property. Miu greed kick in and state that since they are enemies she will take the shoes as war spoils after she defeat her a condition Rimi agree to. However, Rimi state that since her mission is to retrieve the disc, she won't let Miu touch her and march toward the Thor who is holding the disc. Despite her speed Miu manage to catch up with her using the sixth sense virtue and state that there is a huge gap in their experience.
Thor who had enough of them fighting throw them off him. Rimi try to seize the chance and grab the disc, but Thor was holding it to tight and no matter how much Rimi hit him he didn't let go of the disc. However, Thor was holding the disc too tight which caused it to break. Seeing that there is no reason for her to stay Rimi take her shoes and leave, but she promise to finish her fight with Miu in another time.
After the death of the Demon God Fist at the hand of the God Fist, Rimi was shown to be surprised and asked Ogata if it's true which hr confirm it to be true. Ryuto would ask her if she know the Demon God Fist which made her happy that he talk to her. Rimi tell Ryuto and the other s about her encounter with the Demon God Fist.
When she find out that Odin is secretly calling his childhood friend and will meet him that nigh at the aquarium, he asked her if she is going to report on him which she deny saying that she is on his side. While leaving Odin wheel chair couldn't go on top of two steps stair Rimi tried to push him, but he used his skills to make the chair jump and told her that there is no need for her to push him. Rimi is amazed by his determination and wished to of use to him and she state that she would do anything to help him. Later, it's revealed that Rimi has a blog on the Internet where she right a diary of her days and what she will do and the last thing she wrote is that she will follow Ryuto secretly to the place of his meeting with Kenichi, this was because she thought that Miu will be there as she heard Ryuto say her name while talking to Kenichi.
Rimi bumped into Miu, who came to the place of the meeting because she saw Rimi blog says she will be there and was worried about Kenichi, much to Rimi dismay. Rimi demand to know what is Miu to Ryuto. The two engaged in a fight which Miu gain the upper hand due to her nearly going berserk due to her time as the Demon God Fist disciple. As the fight continue Rimi take off her shoes, but even this don't give her any advantage against Miu and the two fall into the water tank and were discovered by Ryuto and Kenichi. After getting out of the water tank Rimi note how she was defeated even though Miu was holding back and there was something different about her from the last time they fought and figure that Miu possess the Ki of Dou. Making her to Ryuto she find Miu is pushing him seeing this she remembers that he don't let her push him and prepare to fight Miu, but Ryuto state that their they can't stay anymore and they should leave and ask Rimi to push him. Rimi was happy that he is allowing her to push him, but she push him too fast and held a grudge against Miu.
Rimi would ask Ogata to train her in order to become stronger fast. Ogata agree and tell her that he likes the look in her eyes as it determine look and tell her that they will be training in the mountains in the dark valley. While in the dark valley Rimi succeed in her training exercise from the first day which make Ogata happy, but when he asked why isshe wearing a gym outfit she tell him that since she was told that she need a cloth that are easy to move in and thought it would make him excited she brought them. However, Ogata responded by throwing the weights that are tide to her over the cliff so she would repeat the training again. While Rimi run down the cliff she remember how Miu was faster than her and she start to run fast in order to surpass her limit so she can become faster than Miu. Later, Rimi ask Ogata if the motivation to become stronger in martial arts forthe sake of someone else is an impure motivation, Ogata tell her everyone have their own reasons and everyone is equal in the world of martial arts. Upon hearing this Rimi state that she is relived.
After completing another training exercise Ogata ask Rimi why is she wearing a school swim suit and she answer with the same answer when he asked about the gym uniform and respond the same way as before. However, this time the swimming suit pealed off of her and she asked Ogata not to look When it's time to eat Rimi ask again if Ogata saw her naked body which tell her again that he wasn't looking and Rimi state that the only and the first one to see her naked body is Ryuto. Hearing Rimi mention Ryuto, Ogata tell her that Ryuto received his training in these mountains too and he successfully awakened his sleeping Dou Ki. After hearing this Rimi remembered that Miu also possess the Ki of Dou and told Ogata about the last time she fought Miu and he tell her that it must have been the effects of the Demon Fist God training that has unlocked her Ki of Dou. Rimi ask Ogata to unlock her Dou Ki. Ogata tell her that there is s high risk in it,but she tell him that she is okay with it and she will go with high risk high return. Happy to hear this Ogata accept to unlock her Ki of Dou, but tell her that if she allowed the Ki of Dou to consume her their will be a high price to pay.
After unlocking her Dou Ki, finishing her training in the mountains and returning Ogata tell the others disciples that Rimi is no longer the same person they knew she is completely someone else. Rimi appear with an emotionless face which make Ryuto worried at first, but henotice that Rimi is actually sleeping. This is confirmed by Ogata who told Ryuto that once her training was finished all what Rimi said was that she can finally see Ryuto and ran from the mountains without stopping to sleep. Ryuto wake Rimi up with a jester clap and once dhe sees him she happily yell that she returned powered up and almost made him fall from his wheel chair. Rimi tell Ryuto that Ogata told her that shehe have a powerful Dou Ki on par with Miu, but when she notice that she is covered with dirt she run to take a shower and while the others discuss how they will face, defeat and kill Kenichi with his friends and the Shinpaku Alliance. Rimi return asking what she missed while wearing just s towel.
The member of YOMI were given the choice for which one they want to be their opponent so Rimi chose Miu as her opponent. YOMI chose to attack when all of their opponents were at the same place at the same time ad the alliance were having fun in an amusement park. After the evacuation of the civilians each member of YOMI confronted their chosen opponent Rimi was with Lugh as his target was with Miu and comment that she will rip Miu to pieces. However, Rimi was in her habit of wearing different costumes as she was wearing the costume of a stuffed bear and thus Miu and her friend didn't know that it was her and felt that the costume was annoying, even Lugh who was blind admit that he find it to be annoying and asked Rimi to take it off as he don't want to be mistaken for an idiot by standing besides her. Rimi take off the custom and start to attack Miu relentlessly, all while repeating her own name.
Rimi and Miu start their third fight. Rimi attack are stronger and faster than before as Miu note this and Rimi state that she can win this battle. As the battle go on Miu note that Rimi didn't just improve in her speed and strength, but also in her techniques. Rimi ask Miu if she become stronger for the sake of love or used martial arts for that love and state that she will definitely beat her since Ryuto is there too.
Rimi become enrage after hearing her call Ryuto by his full name and yell at Miu not call him by his full name. Seeing Miu only takes hits Rimi drop her guard down, but unkow to her Miu was taking off her limiters and managed to counter Rimi who dropped her guard. Miu tell Rimi that she always had to hold back to make sure she doesn't hurt anyone and thought Rimi may look like a normal girl she can't afford to hold back with her and it took her some time to adjust. Rimi state that she will break Miu pretty nose in front of Ryuto (In Japan breaking someone else nose is a symbol of destroying their pride) and the battle continue. Miu revealed that the Demon Fist God training have powered her up and Rimi realized that can't take Miu lightly and decided to take off her shows and throw them away. However, when Rimi try to attack She is surprised that Miu followed her golden shoes instead of fighting her much to Rimi dismay and frustration.
Rimi rush and take back the the shoes and tell Miu that she can take them after she defeat her and then throw the shoes to the top of the castle at the amusement park and state that she fight for love after asking Miu what she fight for. Miu tell Rimi that those who follow the path of the killing fist hurt people and furthermore it they hurt themselves and she should look at what happened to the one she loves,Ryuto. Rimi smile deviously and tell Miu that to gain great power one must be prepared and willing to go through great risk and unleash the results of her training with Ogata on and gain the upper hand against Miu. The fight continue while the two are on the roller coaster ride and Rimi continue to overwhelm Miu while marveling over her new found speed and power and was prepared to finish Miu off only for Miu to counter Rimi by being faster. Rimi demand to know how Miu became faster which Miu tell her that she had to decrease the strength of her punches to make them faster. Rimi says that it's not just that and there is something else and Miu tell her that she followed her Ki as it was so strong, shocked to hear this Rimi got distracted and cased her Ki to scatter and gave Miu the opening to kick her into the water. Rimi ask if this was the result of her training and Miu tell her that it's not as she learned how to do it in their battle right now to which Rimi respond by saying that it will be Miu loss.
Confused for what she heard Miu state that what Rimi said is something she can't let it slide lightly and admit that this is the first time she have a hard time against a girl who is at her age. Rimi also admit that she heard from the other YOMI how Miu traveled the world to right the wrong eith her grandfather, but then asked Miu if she ever sough power for the sake of the one she loves thatshe was willing to sell her soul which make Miu confused. Rimi remember how she meet Ryuto for thr first time and how she trained hard so when she reunite with him he would love her back. Rimi then state that Ryuto like strong women and that why she can't let another woman stronger than her and she is willing to risk anything in order to gain more power and tell Miu that the delay to release her Ki will be her downfall and then she release her Dou Ki and attack Miu.
Rimi start to overwhelm Miu and after bringing her down she moved in and delivered a killing blow that would have killed Miu if she didn't unleash her Dou Ki. However, Miu Ki goes berserk and she start to fight wildly. Rimi and Miu fight across the park which bring them close from the other battles and when they they come across Ryuto he notice them and realize that both of them have activated their Dou Ki, but Miu Ki has gone berserk. As the battle continue Rimi realize too that Miu Ki has gone berserk. However, Rimi told the berserker Miu to bring it on and the world of martial arts isn't so cut and dry that victory is determined simply by explosion of Ki. Rimi strike Miu in her abdomen and tell her that if she ignored the damage she take and focus on the damage she gives she won't last for long, but even this don't get through the rampaging Miu who keep attacking wildly. Rimi come to realize that Miu surpassed her in the amount of Ki and speed and she will be done for if she makes one mistake. However, even after discovering this Rimi still determined to win and state that the proper usage of Ki will always win against a frenzied explosion of it. The battle rage on as the two of them make their way to the same spot Berserker and Kenichi are fighting in it with Rimi gaining the upper hand.
The battle temporary stop with Rimi being the one who is standing on the top and tell Miu that even if she have an enormous power she still will perish as long as she don't know how to use it. Ryuto make his way to their location and when Rimi saw him she cover her tattered cloth abd believe that he finished off his opponent and came to see her "heroic deeds". Rimi ask Ryuto to watch her as she finish off Miu and lunges at her opponent and was on the verge of killing her if not for Kenichi words that reached Miu and caused her to block the finishing blow and gain control her rampaging Dou Ki. Rimi realize that Miu too is move by the power of love. However, Rimi try to attack many times , but her attack were avoid and start to receive hits until she couldn't stand. Rimi seem to know that Miu was holding back to make sure the winds are not fata, Ogata, who came to watch the battles, seem to know this too much to his disgust.
However, Rimi refuse to give up and state that those who follow the path of the killing fist don't lose until they die and ask Ogata to finish teach her "that technique" so she can still keep fighting. Thr technique us revealed to be the same technique Ryuto used against Kenichi, the Roar As One that combines both Dou and Sei Ki. Rimi beg Ogata to teach her how to use the technique, Miu and Kenichi try to stop her, but she doesn't listen to them and keep asking for the technique in order to win. Ogata tell Rimi that he already thought her how to use it when he thought her how to use her Ku in the other way, the Sei way and Rimi tell him that didn't felt that Ki was right as it sink and solidify inside. Ogata tell to hold her Ki inside and make it explode then tell her that the world of martial art was built on and can move forward through noble sacrifices so even if she die from the usage of the Roar As One technique it will not be in vain which Rimi accept it. Ryuto himself try to stop Rimi, but she just turn her face toward him and as keep watch her as she definitely will win and activities the Roar As One.
Using the technique Rimi gain the upper hand as she gain an incredible strength that allow her to use one hand to swing and throw Miu away. Ryuto who know the consequences of using that technique beg his master to stop her. Rimi continue to dominate Miu and tell her that this is the power of her love. Rimi wonder if Ryuto is s watching her and turn an eye to see if does only to see him desperately begging their master to stop her which confuse her and assume that he still have feelings for Miu and assured him in her mind that she will become a strong woman too. However, after seeing the desperate look in his eyes she ad assumed that he doubts her chance of winning and increase her usage of the technique which also increase the strain on her body and attack Miu angrier than before.
Rutyo seeing this beg his master to stop her before the side effects kick in as he is the only one who can, Ogata tell him that he know that, but he doesn't feel like it and by now Ryuto should understand his dream as that's why he became his disciple. Ryuto tell his master that Rimi didn't think through when she used that techniques, but Ogata don't seem to believe that indicating that he know that Rimi did it willingly for Ryuto. The side effect become visible as Rimi muscle fibers began to be torn a sunder and she started to cough blood. Even with this Rimi keep fighting while yelling that she will become strong woman because Ryuto loves strong women. Shocked to hear what he heard Ryuto rush to stop Rimi yell that she had done enough while Ogata tell to give up as even he can't stop her now. Ryuto ignore his master and keep rushing to Stop Rimi. Both Rimi and Miu lunges at each other while Rimi shout at Miu to disappear so Ryuto admire her only. Both punch their opponents and are sent flying away. Ryuto catch Rimi and she almost attack him in a fit of blind rage before returning to normal after seeing him and collapse while coughing blood.
Ryuto stop Rimi from falling and hold her in his arms. Rimi ask Ryuto if she were strong and he tell her that she were. Happy and over joyed that he finally acknowledged her she state that she must try harder from now, but ask why it's getting darker which indicates that she is dying. Ryuto hold her closer and ask her to hang own and she notice how kind he is to her today and she is lucky, then she seemingly pass away in his arms leaving him to scream her name in pain and agony.
Ogata check her pulse and confirm her "death" and tell Ryuto that it wasn't in vain as she is now a foundation for the martial arts to develop and the Roar As One technique will one day be used by everyone and in order for that to happen sacrifices are needed and from Rimi case he had hint why the disciple of the God Fist could control it well and that because he was raised in isolation which made him control his emotions and he should teach his disciples how to control their emotions. Hearing this being said so coldly Miu attack Ogata who easily block and counter by sending her flying away which anger Kenichi who attack Ogata. When Ogata was about to kill Kenichi he was stopped by non other than Ryuto who revealed that he regained his ability to use his legs and wad perfecting his control over his Ki and now can control the Roar As One technique for thirty seconds. After the two fight, fail to defeat Ogata and witness the death of Tanaka at the hand of Ogata, Ryuto sees that the fire is getting closer to Rimi body so he move himself to save her and would have been burn to Ashes with her if not for Berserker who stated that he wish to have a match with him again one day.
After escaping the burning amusement park Rimi is s revealed to be alive ve snd eas introduced to a doctor who knows about the Ki distribution. While in the hospital Ryuto visit Rimi in her room and while her eyes are open she doesn't respond when he call her by her nickname, but when he call her by her real name she respond and says that she was playing dead and ask if Ryuto was worried about her. Ryuto says that he wasn't worried much to Rimi disappointment. When Kenichi and Miu suddenly appear to visit them and ask if they interrupted them which Rimi yell at them that they did as the ruined the moment and are enemies. Miu tell her that since they left Yami they are no longer enemies, but Rimi insists that they are. Rimi cling to Ryuto to show Miu that she is closer to him than her and ask him to take her to the aquarium when they get out. Miu tell the two that the doctor said that there was an outside factor that stop the rampaging Ki of Rimi and without that she would have died. Miu, Kenichi and Ryuto figure that it was Ogata while he was checking Rimi pulse and falsely confirmed her death. After getting out of the hospital Rimi and Ryuto where being checked by Akisami who asked Rimi why was she wearing a nurse outfit and she answered with her usual answer that she think older men like these kind of thing s which Ryuto responded by telling the doctor that he can punish her with a punch.