Yoko arrives after hearing she can win a prize by completing a naughty game. The rules are simple: while talking to her boyfriend on the phone, she must endure a series of pranks without letting him notice. If she survives, she gets the reward; if either of them hangs up, she receives punishment instead. It starts with relentless tickling, then moves to breast teasing that draws dangerously horny moans from her. The challenges only get more intense, so she had better keep her composure.