[Momo's only really seen the vague quest messages regarding that whole situation, so while it does ring a bell, it's not enough of one to make an immediate connection. Still, one part of that sounds like a pretty likely explanation to his minimal-context brain.]

I mean, if there's a huge magical creature sleeping there then that could have something to do with it. Assuming magical creatures give off magic vibes.

[Which he is assuming because this world is weird and he still doesn't get everything about how magic works. It seems a logical enough assumption to him.]