Well, he can't not glance at the man's beautiful scales... But to Robin's credit, he really is trying to behave. The glance is brief and he goes back to focusing on ruining Vincent's life instead of imagining any number of things his current company would not find particularly entertaining.

Besides, with how good a mood Irahl seems to be in, he wouldn't be surprised if the man was showing off his scales in-part to be mean to him. Stunted or not, he is a dragon.

"...Y'all sure this is a bird?" Vincent says with rising incredulity, "Sounds more like some kinda flying nightmare snake..."

That gets a hearty (though odd, in the usual way) laugh out of Robin, which also helps distract him.

"That's not a terrible way to describe them! Their necks are a bit snakelike..." Robin makes a wave with his hand that... Literally could only be for Irahl's or his own benefit, since Vincent can't see. "But snakes only bite if they have to. Geese will bite if you look at them funny."