[Wow why was Sam so upset? Dio hasn't even said anything mean.]

He's a good enough kid. He'll make you happy, I guess. [Because he has to say something nice about Mikado here, right? Though he doesn't really believe for a moment that he actually cares for Sam, so he wouldn't say that.]

And he's very important to me too, so you'd better take good care of him.

[Okay that one was just a joke. Though he supposed he DID tell Masaomi that he'd protect Mikado, so maybe that'd help him do that.]