Wareta Cup wo Modosu ni wa

Keita and Kippei have been in love for over 10 years but started having troubles expressing their passion physically somewhere along the way. Whether they are too used to each other, or just feel too awkward about it, their bedroom is almost dead. But when Kippei breaks a cup they made together on one of their first dates, it allows him to switch places with himself at the age of 18 and spend time with a younger Keita. By revisiting the beginning of their love story, Kippei might just be able to find the answers to his current predicament.