A person who has an unhealthy preoccupation with the female genitalia; a person who actively seeks to have contact with female genitalia through indirect means (i.e. through touching underwear)
When a woman gives two consecutive blow jobs to two different males, and the ejaculate from the first male is still in her mouth upon the second act of fellatio.
I caught Theresa cumdoubling at the work holiday party, Pete was pissed that he was second.