The tag "biversbear" seems to be a combination of two words: "bi" and "versa" or "versatile." In the context of porn video tags, it is likely referring to bisexual and versatile sexual practices.
Bisexual (bi) means that the individual or participants in the video are attracted to both males and females, or a combination of same-sex and opposite-sex partners. Versatile (versa) or versatile refers to someone who is open to engaging in various types of sexual activities and roles, such as acting as a top, bottom, or switching between the two during a sexual encounter.
So, a video tagged with "biversbear" would likely depict scenes involving bisexual individuals participating in diverse sexual activities and roles. This could include group sex, threesomes, or any other variety of sexual encounters that incorporate both same-sex and opposite-sex partners.