A slang term used by a group of teenagers, representing the process of intercourse. The "P" representing "pussy" another slang term for the vagina. P-time simply means the act of a man(or in odd situations a woman whom happens to have a penis) placing their penis in the vagina, for the age old act of sexual intercourse.
"May i interest you in P-time?"
"I would very much enjoy some P-time right now"
"Yo man....did you?....P-time???"