One Sunday morning after a long night at the bar, normal salaryman Yoshida awakens to find his small apartment occupied by a strange high school girl, which is the last thing he anticipates. Yoshida was rejected the previous evening despite finally working up the nerve to confess to his longtime crush and boss, Airi Gotou. When Yoshida returned home in a drunken haze from drowning his sorrows at a bar with his close buddy Hashimoto, Sayu Ogiwara, a runaway high school student, met him. Yoshida agreed when she requested him to let her spend the night because drinking had impaired his judgment. Yoshida now asks Sayu to explain because he has his mind on straight but has no recollection of what happened last night.