Heart Mark Oome.

His step-sister is an erotic manga artist. Reika usually relies on her step-brother, Yuu, for support while she works hard on her manga manuscripts, but once she finishes a manuscript, she can’t control her desires and transforms into a total slut! With her body aroused from drawing too many erotic scenes, she gives in to her instincts, unleashes her desires, and pounces on Yuu without hesitation! Today, just like every other day, she’s determined to milk him dry, shoving herself into every orifice she can find! There’s no resisting her step-sister’s relentless sexual assault…!

Asahi, who secretly harbors feelings for him, has discovered that his stepsister Reika is actually an erotic manga artist! Without missing a beat, Asahi smoothly becomes Reika’s assistant. One day, Asahi calls out to Yuu, but Yuu already knows the lewd atmosphere she’s giving off…! Just like Reika, Asahi attacks him driven by jealousy and lust! After finishing having intense sex with her and heading home, Reika already knows everything…? Caught between his stepsister and the girl he likes, will he be fucked until he’s completely drained…!?