YSN-333 Ah, I want to get my sister-in-law completely pregnant… My sister-in-law who is smaller than me, Tsugumi Serizawa.

The smallness of her body is evident from her appearance. Her brother-in-law would tease her, saying "You're such a little kid," but the sister-in-law herself found that lightheartedness surprisingly comfortable. She had always wanted a younger brother, but due to her parents' estrangement, she thought it was impossible. That became a reality, and because her dream of having a younger brother came true, she doted on her brother-in-law and forgave him for anything, which later led to his rampage... The taboo impregnation play of the sadistic brother-in-law targeting his small sister-in-law！！