俺と冴子さんと寝取られメール

A relationship between student and teacher, nephew and aunt... Kyouichi and Saeko is engaged in a forbidden love.

One day, their immoral conducts was exposed in the school, to none other than a peeping perverted teacher with a camera. "If this is exposed, your nephew is going to be expelled from school.." and with that threat Saeko is being sexually approached. At first only complying to a single time, Saeko is drawn again and again into a relationship she can't escape from. Being a widow but not altogether experienced in sexual matters, Saeko learns of new pleasures without Kyouichi, and lust overcomes her.