Yui is on her way home when a man takes her away. When she comes to, she is fucked by a man she doesn't know. The days of being demanded by the man and used as a masturbation tool continue. However, Yui soon changes... Her cachaetous body awakens to pleasure, and she becomes a slut who begs for a man's cock herself! Her sexually aroused body is panting with pleasure at the insertion of the cock.