Mizushima Iku is one of the 13 main characters in the Starry Sky series
Mizushima - sensei is one of the main male characters in the game series Starry ☆Sky ~ In Autumn~
Name: Iku Mizushima
Name in Kanji: 水嶋郁
Birthday: June 09
Blood Type: B
Seiyuu/Voice Actor: Yusa Koji
Mizushima Iku is a 21 year old who’s still in college and has to do a teaching internship for 3 months. His mother and Kotarou’s mother were friends so Kotarou often looked out after him and he’s the one who helped him get into the teaching internship. He used to be in a music band which Tsukiko was a fan of. Iku had a twin sister died from heart disease while she was in high school. After she died Iku tried to hide his pain by overworking and singing too much until killed his voice and had to retire from the band.
Tsukiko and Iku pretended to be lovers for a month, the month goes by and Iku tells her that nothing has changed and he still thinks that “love” is nothing but a stupid game. Iku tells her that they should stop seeing each other and for a while they basically avoid each other. Tsukiko later hears from Kotarou that he got Iku to come intern as a teacher because his dead sister Yui wanted to be a teacher as well. She also finds out that during their “lovers trial month” Iku had actually been nicer to his male students and actually did his job instead of constantly sleeping in the nurse’s office or getting yelled at by Naoshi sensei.
After hearing this she goes to try to find Iku and then tells him she likes him. She tells him that she wants to change his mindset and that she will come to the rooftop every day to wait for him. He doesn’t show up but eventually one day he does. he confesses that he loves her. 5 years later they move into an apartment together; Iku becomes a teacher at Tsukiko’s old school.