Oral sex is using the mouth on someone else’s genitals. It includes fellatio, cunnilingus, and anilingus. It can be the whole event or a stretch of a longer one. Many people climax more reliably this way than from penetration alone.

Teeth, breath, and rhythm are the mechanical problems. Consent about fluids and about stopping mid-act is the human problem. A tap on the hip should work when speech is awkward.

STIs travel this route. Barriers exist and are underused. Sores on a mouth or on genitals are a pause, not a dare. Wash if you move from anus to vulva or to a penis, or do not move that direction at all.

You can dislike giving oral sex. Say so. A partner who treats that dislike as a dealbreaker is giving you information.