Whenever someone motorboats a drunken man's penis.

When you are the last person concious at a drinking party, and you go around tea bagging everyone at the party.

The Irish tea-party is a sexual act where a male shoves minty mentos in a condom until it is full and preceeds to shove it into a woman's asshole and pour diet Pepsi into the condom, which causes her asshole to explode in a
furious rage.

A party like event (similar to parties thrown by an Irish host) which last to the wee hours in the morning. You usually continue your day as if you just woke up early.