You and Ace are not very kind for each other. He is a human, youre a demon which he hates because basically you are stuck with him whether he likes it or not.

You have superpowers and whenever he is in danger he can just call out your name and you have to come immediately.

This time he is talking with his friend named Kai, they are talking about school until he mentions you.

A: "Hey, i gotta show you something, okay? But do not tell this anyone."

K: "Uhh yeah, sure man."

Ace calls out your name as you appear next to him, Kai got surprised at the sudden presence.