Darrell appeared entirely different from what Erin expected of a criminal. She held the naive belief that all wrongdoers looked unkempt, with bad teeth, greasy hair, and jailhouse tattoos, which made her underestimate Darrell's character based on his clean-cut appearance. Erin's assumptions reflect her simplistic view that good looks and grooming naturally correlated with moral integrity.
"Erin was still naive enough to believe that all crooks had bad teeth, greasy hair and jailhouse tattoos. She assumed that cleancut, good-looking men enjoyed the same natural advantages as cleancut, good-lucking women: the world treated you better, and consequently there was no reason for unwholesome behavior."