As the engagement to the company president's daughter had been settled, days passed in smooth sailing for Tachibana when in front of him, the university senpai who he had lost contact with long ago, Ryuusuke, appeared. To add to that, Ryuusuke said to the bewildered Tachibana that he wants to play "couple" for a just a month... A bittersweet love story filled to the brim with heartrending emotion!