18+ Chotto Bijin de Mune ga Dekakute Eroi dake no Baka-nee

The stepchild from my dad's remarriage is ten years older than me. She's stupid, rude, careless, and quickly resorts to violence, so I call her "baka-nee." But she finds out that I'm using her as fap material...?!

(Source: T.I. Net, translated)

Included one-shot: Fuufunaka Chousain Shimoda Tsutomu