Hika Ryoujoku: The Lust of Shame

Shinichi becomes Megumi's stepbrother after his mother marries Megumi's father. As they begin living together, Megumi starts to develop feelings for Shinichi, seeing him as a caring older brother. Their new family life seems peaceful and full of promise.

However, their idyllic existence soon takes a dark turn. A series of manipulative schemes and traps plunge the siblings into a nightmare of lust and debauchery, forcing them to confront forbidden desires and the collapse of their innocent bond.