This porn video tag is a combination of two terms: "shemale" and "blowjobs". The term "shemale" refers to a transgender or intersex individual, typically one with male-to-female characteristics. In the context of adult entertainment, it often represents performers who have both male and female anatomy, either naturally or through cosmetic surgery.
The term "blowjobs" is a slang term for oral sex performed on a man's penis. In this context, it implies that the shemale performer is giving oral pleasure to a male partner. So, the tag "shemale-blowjobs" refers to explicit adult content involving oral sex performed by a shemale performer on a male partner.