A hidden camera exposes the truth between a man who only wants sex and Yui, a witty 26-year-old who turns every conversation into a joke. Dirty talk makes the guarded, big-titted beauty blush, so he tests the waters with relationship talk, pretends to agree with her views on cheating, and negotiates a mouth-to-mouth drink. She reluctantly goes along, but his caresses draw out an unmistakable response, and the woman who supposedly would not sleep with anyone for any price gradually ends up having sex with him.