"sponsor_barebacked" is a specific tag in the context of adult video content. It refers to an act where one participant, often referred to as the 'sponsor', engages in bareback sex, which means engaging in sexual intercourse without using a condom or other barrier methods.
In this particular tag, "barebacked" implies that the act is unprotected and the sponsor is the individual performing penetrative acts. This term is predominantly used in porn videos to describe scenes where one participant intentionally chooses to engage in unprotected sex with another partner(s). It may also imply that this person is financially supporting, or 'sponsoring' the other participants in the scene.
Note: These tags are meant for adult audiences only and should not be used by minors or anyone who's uncomfortable with explicit content.