In the circumstances of hooking up, a pre-meditated and fully thought out MISTAKE. The main character in a rut roh situation is usually male. He may know and usually does know the following things before the hook up: 1. the girl is disgusting (it wasn't dark or anything) 2. chaos will most likely arise among this main characters female friends or more than friends 3. he will be mercilessly shit on by his bros.
Often times he will try to defend himself by saying he just wasn't thinking, he was wicked drunk and shit happens. But in reality he thought the whole thing through, measured the pros and cons, and when the cons overpowered the pros he knew it was time to initiate rut roh status and go for it.
It is often that rut roh's come in a series and the participant establishes a reputation as a man whore.
Rut Roh has to be said in a scooby doo voice.
Rut Roh participants usually have big uncircumcised penises.
Frank - "Hogey hooked up with vicky...again."
Jesus - "Are you serious? That's disgusting. What was he thinking?"
Frank - "You don't want to know."
Jesus - "That kid's middle name is rut roh."
2. James - "Hey Hogey. How are you? Taking the break up okay?"
Hogey - "You could say that."
James - "What now?"
Hogey - "Do you know risa shifter?"
James - "You mean your ex girlfriends best friend?"
Hogey - "...rut roh."