Board Thread:General Discussion/@comment-17276108-20131126163635/@comment-24255636-20131205181513

1. Maybe Rigby is jealous of Mordecai and doesn't want him to be in relationships anymore because he wants Mordecai to focus on him only (it's a bro thing)

2. He doesn't want to see Mordecai depressed if he gets screwed by another girl

3. He COULD have a crush on Mordecai (look there's a possibility, people)