Synopsis: Onee-chan ga Kita

Tomoya Mizuhara takes center stage in the storyline after his father remarries and he gains a new older sister named Ichika. However, Ichika's behavior is strange, and her intense affection towards Tomoya appears questionable. In addition, Ichika's friend Ruri claims to be a sadist, while her friend Marina, who is of quarter-Japanese descent, possesses a curvaceous physical attribute, which adds to the complexity of the situation.