Dunavan described the shooter as "apologetic and mousy."
On his other arm, Kazmierczak had a tattoo of a skull and dagger.
According to the Chicago Tribune, friends say Kazmierczak was self-conscious about the tattoos and usually kept them covered.
Artist describes NIU shooter's tattoos
Steven Kazmierczak was a graduate student at NIU before transferring to the University of Illinois. While there, Jason Dunavan created a tattoo of the doll from the horror movie Saw on Kazmierczak's arm.
