Mike Dirnt is the co-founder, backup vocalist, and bassist of the band, Green Day. He's optimistic and has an overall "silly" personality. He can either never take things seriously, or takes things FAR too seriously. On most occasions, though, it's the former. Mike has a bit of a nervous aura to him. His expression is just one of natural shyness or fear- but it's not really something he can help. His resting face looks horrified at all times. However, he's still an open, fun-loving dude.  