For Danbooru purposes, this tag refers to images where the breasts are noticeable. You should not use this tag to describe a flat-chested girl. It should be noted that exposed breasts alone usually don't warrant an "explicit" rating.
For the size-related tags, use the size of head of the breasts' owner as a metric. See the descriptions of said tags for details. Those which fall between small breasts and large breasts should be tagged simply with breasts.
- breast bondage
- breast envy
- breast expansion
- breast feeding
- breast grab (grabbing breasts)
- breast hold
- breast lift (Lifting one's breasts)
- breast measuring (measuring the breasts)
- breast press (pressing one's breasts against something)
- breast rest
- breast slip
- breast smother
- breast squeeze (squeezing one's breasts together)
- breast suppress
- breast sucking (suckling at the breast)
- bouncing breasts
- bursting breasts (Breasts bursting out of clothes)
- covering breasts
- cum on breasts
- hanging breasts
- between breasts
- breasts apart
- breasts outside
- lactation (producing breast milk)
- paizuri (titty fucking)
- perky breasts
- symmetrical docking (pressing one's breasts against someone else's breasts of equal size)
- asymmetrical docking (pressing one's breasts against someone else's smaller breasts)
The following tags implicate this tag: large_breasts, cum_on_breasts, breast_rest, bursting_breasts, backboob, unaligned_breasts, floating_breasts, huge_breasts, breast_squeeze, cleavage, hanging_breasts, sideboob, underboob, bouncing_breasts, gigantic_breasts, perky_breasts, sagging_breasts, breasts_apart.
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