Eris, a Catian alien living in Kio Kakazu's house, sets out to learn how Earth games work. Hoping to understand humans better, she tries out board games with Kio and the girls who have feelings for him, convinced that every game needs something at stake. Manami proposes that everyone put up a treasured item, and each round's winner claims one as a prize. The wagers turn embarrassing once the Catians learn that clothing can be bet as well. Aoi and Manami want a special item Kio has put up, but their priorities shift when a DVD of embarrassing scenes of both of them could end up in the wrong hands. Expect a single-episode sci-fi comedy OVA with ecchi and romance elements.