Coworkers Yotsuha and Yuta dislike each other because their approaches to work are complete opposites. After a business dinner causes Yotsuha to miss the last train, she reluctantly spends the night at Yuta's place. More drinks turn a work discussion into sexual banter, and their competitive insults finally provoke an unexpected challenge: if they have so much to say, why not test their compatibility? His cock fits her deepest spot so perfectly that she experiences the best orgasm of her life, and despite still insisting she does not like him, she keeps demanding more sex.