Moustaches Monthly is Pops's magazine he gets in the only mail. Benson assigned Mordecai and Rigby to give Pops his latest "Moustaches Monthly," but Rigby put it in between the couch cushions and they didn't find it until weeks later. After Mordecai and Rigby played "Rock, Paper, Scissors" to see who has to give Pops the magazine, Mordecai lost and had to give it to Pops, but while doing so, he sees Pops naked and also sees his "junk mail". The magazine is also the first thing Mordecai remembers in his memories.
The cover is black, with a red border. It has the word "Moustaches Monthly" in red, and "Special Handlebar Issue!" in white. It also shows a drawing of a man, with a long white mustache.
- Despite being called "Moustaches Monthly" the correct way to spell it would be Mustaches Monthly and also Mordecai just calls it Mustache Monthly without the "s".