Crona is a special character.  "They"(Their gender is never confirmed because in the anime he is a guy but in the manga its leaning towards she's a girl but for simplistic sake they are neither because Crona isn't a person its an homunculus in this iteration.) are the demon weapon made from Medusa.  

If it all came down to one duel between the main cast Crone is the strongest but if it came to talking to anyone normal Crona cant do that as it cant handle basic human emotions from years of torment from experiments from medusa and years of being forcefully injected with the cursed black blood Cronas brain should be mush...But its not.

Crona has one person or things with it at all times and that's

their weapon Ragnarok...who beats the shit outta Crona all the time.  

Crona was a bullied thing all its life till it met the only person to be nice in the form of Maka.  She led Crona to understand friendship and basic human decency. 

Crona is a broken soft spoken creature who becomes a person. BASICALLY PINOCCHIO. Also I added Gorgon because it is still medusas creation so I would assume Crona's full name would take after its parent. 

Looking for someone who can have some dead pan voices with some dry humor in there. 

Goodluck.