Yuusuke's a college student that lived alone ever since his father and mother divorced but his life will change once his father remarries a beautiful widowed woman and he suddenly gets a step-mother. Accompanying his step-mother is also her daughter, Yuusuke's new step-sister.

Yusuke's been very naughty. He's seduced his father's fiancee; transforming her into a debased slave to his own twisted desires. But as his hold on her tightens, his sanity slips, and the forbidden family fun descends into a nightmare of lust! Trapped in madness of their own creation, they will pay the ultimate price for a stepmother's sin!<br><br>
(Source: RightStuf)

Yuusuke Yagami