deep-throat

verb1

1. •
   (vulgar) To perform fellatio or irrumation so that the entire penis is inside the mouth; often penetrating into the oesophagus, requiring the suppression of the gag reflex.

   • After several minutes of deep-throating Derek, Darcy pulled his slobbery cock from her mouth and began licking her own saliva off it. — 2021

noun1

1. •
   A secret informant possessing valuable information, especially one who stays secret long after the incident in question is concluded.