My girlfriend has kept me on a frustrating stretch of abstinence, so I suggest a hot-spring trip in hopes of finally having sex. To my surprise, her mother Yuka comes along. When my advances only cause an argument, I head to the bath alone and unexpectedly find Yuka already there. Her sensual body in the steam overwhelms me, and I forget all about my girlfriend as I eagerly throw myself at her, beginning an affair filled with sex and creampies.