Megumi Shimizu is a 15-year old girl living in Sotoba. She always felt like she didn't fit in the village where everyone knew one another and criticized the way she dressed. She felt like she was better off in the city and it was her dream to go to the city and become a star. Her only friend in Sotoba is Kaori Tanaka, who she actually doesn't like at all. Megumi has a unrequited love for Natsuno Yuuki, a boy the same age as her who moved to Sotoba from the city. Like her, he
also wished to leave Sotoba as soon as possible. Megumi writes him a late summer greeting card but she's too shy to post it. In her free time, she sits near Natsuno's bedroom window in the bushes admiring him from afar.
When a new family moves into the Kanemasa mansion, Megumi is intrigued. She decides to visit but never returns home. A search-party is organized for her and after searching they discover an unconscious Megumi in the forest. The doctor concludes that she suffers from anaemia but she should be fine.
However, a few days after Megumi dies of heart failure, shocking everyone.
Megumi is dead
At Megumi's funeral, Kaori presents Natsuno the late summer greeting card but Natsuno refuses to accept. When burying Megumi, Kaori leaves a present in Megumi's coffin which she was planning to give her. After Megumi's death, Natsuno begins to hallucinate and thinks he still sees Megumi at night watching him from his window.
The attack on Tohru
After receiving an invitation through Tatsumi for Tohru Mutou's house, Megumi and Tatsumi visit late at night while Natsuno is staying over. Megumi enters Tohru's bedroom where both boys are sleeping. She says she hates Tohru for being closer to Natsuno than she ever was. She reveals her fangs and goes in for the bite. Natsuno wakes up covered in sweat and believes it was all a dream. Or was it?
Digging up Megumi's coffin
When Tohru dies several days later, Natsuno knows that Megumi has risen from the dead. He gathers Kaori and her
younger brother Akira, who both were already suspecting something of a supernatural nature was going on, to dig up Megumi's coffin and confirm she's truly dead. And they are right, Megumi coffin is in fact empty.
Megumi facing Natsuno
That evening, Megumi and other vampires are ordered to attack the Ozaki clinic in order to kill Setsuko Yasumori. Megumi knows Tatsumi has ordered another vampire to kill Natsuno, because of his suspicions, and goes to Natsuno because she wishes to do the job herself. She runs into Tohru, now also a vampire, who had the order to kill Tohru. But he couldn't go through with it. Megumi decides to do it herself. She runs into Natsuno but Tohru does eventually end up biting him instead.
Megumi and Tatsumi
After this, Tatsumi orders Megumi to go after Kaori and Akira's family starting with killing their father. She does so and threatens Kaori.
Some days later, Natsuno also dies and Megumi hears that Natsuno is cremated because he originally came from the city. This news devastates her because she knows that Natsuno can't rise from the dead if cremated.
Where it all began, where it all ends
After the humans finally discover the vampires, a war breaks loose between the humans and the vampires. Megumi decides to escape and wants to go to the big city. While crossing the road, she sees Natsuno waiting for the bus, distracting her. She is ambushed by the humans who run over her with a truck. Megumi is still alive and tries to escape. In the anime, her head is crushed by a tractor and even now she's still moving. She is staked by the humans. In the manga, she is staked with around 5 stakes sticking from her chest.