Pelching (or to pelch) is an unfortunate side affect of people who have failed to mature mentally. It is the act of trying to reverse actions taken in a game done by one who cannot fathom the concepts of losing or fair play.
Sylvia: Knight to queen's rook.
Andy: Hey, I didn't see that or I wouldn't have moved my pawn. Give me back by rook.
Sylvia: Hey, no pelching!
When you fuck a house up so bad from a party it causes future parents to say no to their kids when asked about having a party
“Hey did you hear about the huge fucking party mike had?”
“Nah what happened?”
“Like 150 people showed up and were phelpsing the fuck out of his house”
“Wow! Holy fucking dick cheese!”