H na Gishi Series The Animation

Takashi begins living with his new stepsister after his father remarries, initially dreading the awkwardness of sharing a home with a girl—even if she's just a stepsister. But when he first lays eyes on her, he's utterly stunned: her name is Alice, a stunning beauty hailing from Northern Europe. While he's thrilled to have such an adorable stepsister, the sight of her massively overflowing breasts ignites a whirlwind of confusing, lustful urges deep inside him. Nevertheless, as he observes Alice's sincere efforts to blend into the family, Takashi fights to bury his filthy fantasies and play the role of a dutiful big brother. That fragile barrier shatters irrevocably one fateful day when he stumbles upon her completely nude, unleashing a torrent of pent-up desire that he can no longer contain...