Actually, Mikoto, a high school student who lives alone in an old apartment, just started dating Murakami-san, a university student who lives in the next room. Living under one roof, she's happy that she can be lovey-dovey every day with her boyfriend, but reality is somewhat different...

From Aerandria Scans: 
Mikoto, a high school student who lives alone in an old apartment, and Murakami-san, a university student who lives in the next room, are a couple. She should expect every day to be lovey-dovey with her boyfriend, yet troubles after troubles keep on happening!?

Contains three short stories: 
Cream Caramel 
Because her parents are transferred away due to their jobs, Mikoto, a grade 11 student, starts living alone on 100,000 yen per month. But the place she lives at is a horribly old apartment... And the one living in the room next to hers is a super cool boy...?! 
White Summer 
Mana and Shou have to go their separate ways after graduation, will they be able to stay together when they're hours apart? 
There Are Days Like That, Too 
Sonomi has been in love with Ikuta-san since she was in the seventh grade, four years before this story takes place. Ikuta-san suddenly starts working at her uncle's cafe, and it seems like Sonomi might have a chance to be his little sister, since he's been going out with another girl for those same four years that she's loved him. 
(Source: Intercross and Forbidden Garden)

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