Mion, the stepdaughter of her second husband, has recently become much more mature. After her stepfather massages her injured leg during club activities, she begins to experience adult pleasure with oil mixed with an aphrodisiac. When her mother is out, she is trained with the aphrodisiac. Eventually, her body becomes so desperate for the aphrodisiac and her stepfather's dick... She convulses in agony so much that her thin waist seems to break! "I'll do anything for you, stepfather, so give me more."