General: underboob (Version 4)
When a girl is wearing clothing that is designed to expose the bottom of the breasts or when wearing clothing that is lifted so that the bottom of the breasts are visible. Typically, to be considered "underboob", the nipples are not visible.
(Partially copied from Danbooru)
(Partially copied from Danbooru)
Updated by Belguim about 13 years ago