Kashima is roommates with Sora, an airhead who can't take care of himself, so Kashima mothers him a lot. One day they both have to go to a college party and Kashima drinks a lot so that Sora can't. When they get home Sora loses control of himself and takes advantage of Kashima's drunkenness.
Totsuzen, Doukyonin ni Marking Saremashita