Oral to completion (OTC) involves stimulating a partner orally, whether via fellatio or cunnilingus and continuing the stimulation until the recipient reaches orgasm.
Oral to Completion (OTC)
More About Oral to Completion (OTC)
Often, oral sex is treated as a precursor to intercourse. Giving oral to completion can make it into more of the main event.
Orally stimulating a partner to orgasm, or being orally stimulated to orgasm, can be intimidating for some people due to the extreme intimacy of the act and should be negotiated between partners.