[My authorial fiat says it can be pet, I refuse to believe it can't. I make the rules here. Katsuya extends a hand up, Helios entangling its claws around his hand in what's probably a steadfast gesture]

A month ago when I and other two were confronted with a deadly and supernatural situation, Helios came to my rescue. We all gained Personas and since then we have been using them to fight.

[He's...pretty sure it's because in high school he played a silly game about channeling Personas, but that was like nine years ago and it's chilling to think that, if he hadn't, he probably would be dead right now]