Overall, it's known as a description for "shinya anime waku" (late night anime slot) shows.
If it's airing late at night around the 24~26:00 time slot (it can be on a large network, obscure UHF channel, or BS/CS satellite - doesn't matter) and is slotted for only 1 or 2
kur at most, it is likely to have an original ending. Anime based on ero/bishoujo games ends satisfactorily, however it tends to choose one character over another (usually the main heroine, but not always the case).