Chiaki is extremely sensitive to tickling, reaching an orgasmic state at the slightest touch. On the other hand, Rika has a masochistic personality and is highly resistant to normal tickling, raising the question of whether she can endure Chiaki's intense tickling attacks. The tension between the two gradually builds, transforming their laughter into screams, and eventually into pleading moans begging for mercy. As a MEDUSA production, the erotic progression is the main attraction.