He looks frightened there. It's important to remember that it is doubtful that Karina saw THAT "frightened" face when he punched her in the mouth so hard it knocked her tooth out. This was a brutal, brutal crime. He may be frightened for himself today but he showed Karina no mercy at all.
A few lapses in Dads story as well. This kid is supposed to be a great student...but he is not, to our knowledge, in any type of further education...at 20 years old. HE was he going to "become a social worker?" Was the tooth fairy going to grant him credentials?
He seems to have been lurking around the backyards of Howard Beach...does he NOT have a job? Dad obviously does not live at "home".,,so I question how much his "story" will really turn out to be accurate.
If his DNA ai's under her fingernails, etc...let's keep what Karina suffered in forefront of our minds.
He savaged her.