The Butter Effect 

Used when explaining the story of a girl who had sex, even though she told you repeatedly that she was going to wait until marriage. The saying goes "She fell prey to The Butter Effect- things got hot and she spread easily"

Dude that girl said she'd never do it with anyone

Yea, she fell pray to The Butter Effect.

The Butter Effect by HeyitsAC September 26, 2008

the peanut butter effect 

A lingering smell.

HISTORY
When one eats peanut butter the smell of peanut butter sticks with them for a extended period of time even though all evidence of the peanut butter is gone.

Often related to other items of similar consistancy. (read:feces)

Example 1:
A dog does his business outside and comes in to sit beside you. The dog smells very much like his dirty business even though his anus is completely free from 'cling-ons'. This is the peanut butter effect.

Example 2:
One is doing laundry and notes the 'peanut butter effect' on a pair of underwear. The underwear may only inhibit a foul smell or may be accompanied by 'skid-marks' after being well used.

the peanut butter effect by Christine P. May 4, 2006