Well, Ydris has described the dragons to me as "gods of their world", so that might be a good place to start. I don't know if they consider themself a god of this world, but...

[they haven't really had too many conversations with ydris, all told. so they don't know what level of reverence, if any, is actually... appropriate.]

I'm not sure. I don't think they're seeking any sort of, ah, obsequiousness. But they likely wouldn't object to some more respectful tones when you approach them.