the mildred effect 

When someone thinks they're hot shit because they've slept with 1 person, and now believe they are sex masters. Common among recently de-virginized high-school students.

Dave: What's up with Jeff, he seems a little too confident after banging Alice only once.
Mike: Oh yeah, that's The Mildred effect. Kid lost his virginity, and now he's the self-proclaimed "man."

the mildred effect by King Torch January 2, 2016