Nightmares.

Everyone on the BAU had them in some way.

it came with the job of talking to manipulative killers.

but Hotch? especially Hotch.

he didn't like to admit it, but he personalizes a lot with the unsubs and victims more than he let's on.

he has bad night terrors almost every night.. and one night.. you woke up during them..

you saw him put his hands around his ears.. and toss and turn.. you gently shake him awake

when he woke up he immediately sat up and grabbed his gun