A subtrope of Room Shuffle.
A stock excuse for going out, when a character either doesn't want to give the true reason or is leaving not to return, is "I'm going to the store". In Manga, Anime and other Japanese media, the store in question is likely to be referred to as the konbini; i.e., the local convenience store open at practically all hours.
One reason this trope is a lot more prevalent in [...] [tvtropes.org]