Rookie is an EPF agent that has little experience with the EPF, dubbed his name as a beginner. He showed up in many EPF and former PSA missions where he needed guidance from his coworkers because of his inexperience and slowness in missions. Sometimes he takes a break from his EPF work to join penguins in parties to relax himself. He shows up in the April Fools Party every year to share his jokes with his followers. At other times, he helps G to fix up things that were vulnerable to the EPF mainstream.
Figure 1 Rookie’s outfit is different then what he wears in EPF and former PSA missions. Taken from his special appearance in January 2012.