DVAJ-371 Aoi Kururugi lives a barely incestuous life with her younger sister who allows her to penetrate up to 3 cm of her tip.

An older brother notices his younger sister Aoi's suspicious behavior. - When I questioned him, he told me that he had been practicing wearing a rubber band with his brother's cock. - Since then, he has been helping Aoi practice wearing a rubber band, but... it's too painful to leave him erect, so he asks Aoi to help him ejaculate. - Unable to endure just handjobs, they give blowjobs and pussyjobs... When they finally reach the point where they can't penetrate each other, they make a rule that ``If the tip is 3cm long, it's not considered sex even if you insert it,'' and they start having neck sex over and over again. - . - Eventually, just having the glans inserted wasn't enough, and they started wanting to fuck each other deep into their vaginas.