Bond levels...? You're really incorporating that D&D book into your lexicon, huh.

[ Somehow she really doubts that her petting her ghost cat sometimes makes it any stronger, but it's hard to gauge when your Persona's stupidly strong and yet you never fight with it and so you can't tell. ]

Kurusu did say something about that, though, how you have to get along with your Persona in order to use it the most efficiently. Which makes sense, otherwise they could attack, and they're the stronger ones.