[ He likes this playful new friend he's made. Sylvain has a good answer, and most humans assume all spirits are ready to eat them, so this more open-minded response is refreshing to get from a stranger. It does make him want to tease him more, but Seimei honestly doesn't need very much encouragement for that anyway. ]

Then we'll try not to let them eat you.

[ Maybe. It's probably unlikely for them to need to fight off malicious spirits, but they can never be sure. But dealing with strange magical situations is pretty normal for him. ]

That's right. I wanted to find out who they are and what they want. Then maybe we can get them out of the mirrors too.