A rather literal term referring to the action of deep diving in a common householdunderground storage tank containing fecal matter.
The use of this term is a great term to use to insult someone!
(see below)
"Diving Deep" happens during sexual intercourse where the man tries to push his penis far into the female's vagina.
Alone, to take a "dive" means to penetrate. So when someone dives, they're having sex. But when you dive deep, your whole penis is probably inside of the woman.
Just like when someone says "I went deep" or when a female says "He's so deep". They arent talkin' about personality ;)