Munyu

Toshi is an ordinary high school student. With his parents rarely around, he spends his days being cooked for and tutored by his beautiful neighbor, Yuu-nee. She’s kind, caring, and the very picture of a perfect working adult. whenever games are involved, she becomes a completely different person...!? She's not playing around! She will rage, strip, and do whatever it takes to win!

An omnibus of assorted childhood friend stories, from the duo that brought you "Asa made Jugyou Chu!"

Kagami Yuuki has managed to become a scholarship student in a high-class high school. Unfortunately, thanks to his gender-ambiguous name, the teacher Kakinozaki Ayana has registered him as a girl! It's apparently an uncorrectable mistake, so now Yuuki must live in the girl's dormitory of his new (co-ed) high school. At least Ayana's willing to take responsibility for her mistake; she volunteers to be his roommate. As one would guess, he and Ayana must make sure none of the other girls in the dorm find out he's actually a boy. Therefore, except for when he's in his classes, Yuuki has to cross-dress, or else both he and his teacher will be kicked out of the school and dorm! Link: AnimeNewsNetwork (OAV)