Yuu Saigawara lives with his stepsister Reika , a shut-in erotic manga artist who uses him as a live reference for her explicit work. Whenever Reika finishes a manuscript or needs inspiration, she subjects Yuu to intense sexual encounters to ensure her art remains authentic. Despite his desire for a normal life and his friendship with a classmate, Yuu remains trapped as his sister’s primary source of creative material.

Asahi , a girl who secretly has strong feelings for Yuu , discovers that his step-sister Reika is actually a popular erotic manga artist. Without hesitation, Asahi becomes Reika’s assistant to get closer to Yuu. Driven by jealousy and pent-up lust after seeing the lewd atmosphere, Asahi transforms into a hypersexual mode just like Reika. She aggressively seduces and attacks Yuu with intense sex. Meanwhile, Reika finds out what happened and gets involved, turning the situation into a competitive, non-stop threesome where Yuu is relentlessly drained and squeezed between the two horny women.

It’s the worst after all… I woke up in the middle of the night because of a presence… and I already knew who it was…

“My sister and I have become your pets, big brother.” Sisters Reina and Aina fall in love with their stepbrother Shota, but at the same time, they are thoroughly trained by him. The sisters are completely corrupted by him as he indulges in perverse play wherever they are… but one day Aina receives a love letter from another boy, and Shota becomes interested in another woman… will the sisters’ training relationship fall apart?

Shota, a stepbrother, is very affectionate towards sisters Reina and Aina, who he grew up with like close siblings. Day by day, he becomes more affectionate towards Aina… and eventually even crawls into her room at night!?

“I want to be fucked like my sister!” Aina finds out that her sister Reina has become her stepbrother Shota’s sex toy. Unable to resist Reina monopolizing Shota, Aina finally sneaks into Shota’s room at night…!?