[He didn't have much of a choice but to believe Hiccup at this point. Especially that 'best friend not being a dragon anymore' part. Time to focus on other things!]

That's cool that you know a dragon! I know a cat sith, but that's about it.

[He shrugs, not really too concerned with particular questions. He's willing to learn as he goes, but he appreciates the help.] ...You're being helpful enough. This place is weird enough as it is.