[I want to play with Karin-chan's nipples!] When I was a child, my parents remarried and I had a step-sister.They got along well and became like a real brother and sister, but...the older brother became excited by the growing and expanding breasts and started observing them.Then I got a peek at her erect nipples and the urge to touch them exploded!When he can't hold back and starts to play with him, he starts to scream "Big brother, fuck me!", but his sexual desire goes wild when he sees him twitch every time he stimulates his sensitive dick!The momentum escalates to nipple kneading SEX without stopping!The younger sister is so excited that she cums over and over again, and accepts her older brother's lewd sexual development training."I'll make Karin-chan grow into a premature ejaculation type!"
