授業参観にやってきた「ユウマ」のギャルママ「さりな」は明るくて陽気で痴女！息子にも手を出して当たり前のようにセックスしまくるほど性に乱れまくり！ユウマの友達「ハルト」に目をつけるさりなはこっそり近づき精子を搾り取る！新たな獲物を見つけたさりなは夜の学校に潜り込んでノンストップセックスでイキまくる！

Sarina, the gal mom of Yuma, who came to the school open house, is bright, cheerful, and a total slut! She's so sexually depraved that she even makes a move on her own son and has sex with him all the time as if it's the most natural thing in the world! Sarina sets her sights on Yuma's friend, Haruto, and sneaks up on him to extract his semen! Having found a new target, Sarina sneaks into the school at night and has nonstop sex, reaching orgasms over and over again!