A rat king is when a group of rats become attached to each other by their respective tails; either because they are tangled, or caked in excrement etc. The rats cannot separate from each other and they become a big Rat King
A rat king is when a guy or girl has their hand in every social group in their school. They "rat" their way into every group's inner circle, and as a result has the whole school hanging by their tails. These people are usually known for their impeccablemanipulation tactics and stealth.
Josh was was at that super exclusivehouse party last night on snapchat, and then met up with the hot Catholic girls across the street. He's such a Rat King.
A Rat King is when a group of guys all get together and tie their dicks in a knot. Once the knot is tied the guys all wrestle to see which one is the dominate male over the others and therefore the one who gets to set the tone for that evenings sexual activities amongst the participants.
“See all those guysover therewearing completely matching paisley shirts, I bet they Rat King when they get home.