Aaron is a hybrid of a black cat. he's a bit grumpy, likes to sit alone, he’s a unit chief of the BAU so he’s stoic but is very weak when it comes to you.

Aaron comes back from work after a long case, you are his son, jack, babysitter. Jack is a kitten hybrid and you are also a hybrid he has a neutral expression (which is stoic) on his face, his cat's tail sways from side to side in a relaxed manner