Xel gives him an indignant look. "Mou, what am I, then, a pile of dust?"
"Ara!" he exclaims, wide-eyed. "Is there a mouse? Oh, then let me only find it..." With a determined expression, and a fine disregard for Iago's state of habille, he begins the hunt, not only seeking with his hands but scenting it out.
"Oh, good," he smiles, nuzzling in. "I was afraid you'd take it as an insult, ne." Iago, he knows, didn't need that overtly explained, but he thought it might be better to say it out loud, as an apology for not offering before since it apparently wasn't an offensive offer.
He does invite it, but then, he also tends to wallow. Xel tries to preserve a fine balance of patting him onna head and smacking him with a slipper. ;)