Onee-chan ga Kita

Onee-chan ga Kita is a lighthearted comedy anime about the chaotic and heartwarming adjustments of a newly blended family. The story centers on Tomoya Mizuhara, a reserved 13-year-old boy whose life is turned upside down when his father remarries, and he suddenly gains a 17-year-old stepsister, Ichika.

Ichika's affection for her new little brother is immediate, enthusiastic, and overwhelmingly intense, often blurring the lines between sisterly love and comedic obsession. Tomoya's attempts at a normal school life are further complicated by Ichika's friends: the mischievously sadistic Ruri and the charismatic, quarter-Japanese Marina.

The anime explores themes of family, acceptance, and the unpredictable bonds that form between siblings, all wrapped in a package of over-the-top humor and situational comedy as Tomoya navigates his new life with his relentlessly loving big sister.