Cute porn actress Satomi says she can orgasm while masturbating but rarely during partnered sex. To test that claim, the production brings in a veteran porn actor and promises her a reward if even his technique cannot make her cum. The challenge begins, but she is soon moaning with obvious pleasure. One orgasm quickly becomes another, proving that her previous partners simply lacked skill. She misses out on the planned prize, but the repeated orgasms turn out to be an even better reward.