Forum:Ally of Justice Catastor vs. Jurak Titan

I was playing a Jurak deck against a frog synchro deck, and he had an Ally of Justice Catastor. The next turn I got Jurak Titan on the field, which cannot be targeted by trap effects or monster card effects. I was wondering if Jurak Titan attacked Ally of Justice Catastor if Jurak Titan's attack would go through because of his effect. Or, does Ally of Justice Catastor's effect not target?