Double Helix of Her and the Older Sister

Kaname is a young boy living with his older sister, surrounded by the women in his life. His days are filled with the presence of his sister and a girl he secretly admires, but their relationships are far from ordinary. As Kaname navigates his burgeoning desires, he finds himself drawn into a tangled web of intimate encounters that blur the lines between family, friendship, and romance.

The situation escalates as Kaname becomes involved in a series of explicit group performances, where the boundaries of propriety are pushed to their limits. His sister and the girl he likes engage in yuri interactions, further complicating the emotional dynamics. Caught between his feelings and the escalating physical entanglements, Kaname must confront the consequences of his actions and the true nature of the bonds that tie them all together in a double helix of passion and confusion.