My Mama's Best Friend Ruri Saijo

Ruri is entrusted with babysitting and house-sitting while her married friends are away on a trip. She discovers a pink vibrator that seems to belong to her friend. Overwhelmed by the excitement and sense of guilt from seeing something she shouldn't have, Ruri can't suppress her desires and presses it against her crotch. Then, the child who was secretly watching the whole scene... The boy, aroused by the first sight of a woman's lewd figure, goes into an unstoppable frenzy and begs Ruri to teach him.