When playing drinking games that players can define rules, the little man rule is usually stated:
Every time you have to drink (not casually) you must pretend there is a little man sitting on your drink which you must remove and replace after drinking. Failure to do so will result in further drinking as a penalty.
Victoria picked a red 5, she has to drink for 5 seconds. "Don't forget the little man!" Victoria thanks Diana while the guys hope she at least has a low tolerance..