Weeeeeell, a Knight if an exploitation class. Does your world have a concept of knight? Basically that. Go be a protector and fighter and all active. You may have a limit on your aspect, but what you DO have, you use hella well.

As for Heart, it's emotions, feelings, and the whole soul itself. Not quite the neg and pos feels, so much as all of them, and the core of the true you without all the other shit gettin' in the way.