Anitomo (2018 Japanese TV series)

Sota Nishino (Ryusei Yokohama), a handsome high school senior, is close friends with Yukihiro Nanase (Tsuyoshi Furukawa). During a private conversation in Yukihiro’s room, Mai (Matsukaze Risaki), Yukihiro’s naive younger sister, overhears Sota commenting on her attractiveness. Inexperienced in love, Mai gradually begins to know Sota better, and their interactions are initially awkward. As they spend more time together, their relationship slowly develops, with romantic feelings emerging between them.