With a competition approaching, Mirai, a member of the track and field team, decides to undergo special training to strengthen her legs. She is ordered to do long periods of squatting in a crab-legged position, in the name of strengthening her lower body. Taking advantage of the Mirai that no other members are around, the coach strips the sweaty Mirai and starts touching her with lewd hands. Realizing that her legs have reached their limit, the coach waits for his cock and tells her to lift her hips so that he won't insert it. She resists desperately, but at her limit he finally inserts it. She is unable to move due to the excessive pleasure and the relentless thrusting begins.