Protagonist Tsukinari the girlfriend Sayuri of elder brother, couple of handsome man and beautiful woman who person envies. However, as for Tsukinari, the opposite it doesn't have the ability and the growth of the body and the heart is late with it, it is boy of not bright. The elder brother worries such him, it gets a tutor Sayuri.

A certain day, tsukinari that touches the body of Sayuri that has taken a nap during the lesson for no special reason, it experiences a sexual awakening typical to the blitz. The touching like the impulse to feel nauseous the body of her corpulent, the penis is inserted! Sayuri that wakes up to painful of the virgin loss, it turns pale to the sense of hopelessness.

Tsukinari from it forcibly calls Sayuri many times, as the lust orders it. Resisted Sayuri also at first, it is dyed to the intensifying pervert play before it continues for a long time, It falls down to the foolish face woman who desires the inside ejaculation, the desire to the elder brother weakens too...