Similar to the saying no homo. No bromo is said after a sentence that can make one appear to be a bro. Mentioning subjects such as Dave Matthews Band, Phish, Dane Cook, and cheap American beer such as Natural Ice and Keystone in a positive light should be followed by saying "no bromo". Unless of course, you are a bro.
1. I'm going to my boy's house to play some pong and drink some Natty Ice, no bromo.
2. I thought Dane Cook was hilarious in Employee of the Month, no bromo.