Ignis holding him back was probably a big reason of him calming down, but he was still on edge and glaring at the tiny person. She did just punch him in the face!

"Like I've been saying all day, a girl with cat ears somehow got into our world and gave it to me as a reward for beating Garuda. YOUR Garuda," Noct said, rather flatly. "I'm 'blessed' enough by the presence of the astrals, I don't need yours on top of that."