Blackheart

A Blackheart doesn't have a black heart.

It's a person who can see straight even tho their mind is in a void. (You are in a bad/dark place)
They are sensitive but that doesn't make them weak at all.

It is the opposite. It is their strength.
Empathy is a possible weapon.

"How are you able to get through this without losing yourself?" - "Well, I'm a true Blackheart."