Yeah. And Sora is definitely not a pint sized girl with black hair. It'll be ... a little confusing until he works through the cognitive dissonance.

Xemnas may well be playing very nice. For a while. After all he has no control here, no way home and most importantly, none of his power. It's kind of hard to rule with an iron jackboot when your pets can push you over!! (Plus the whole heart thing, that's gonna take adjusting to.) If Xion's careful, and wants to keep things pleasant, she might be able to very easily stay in his good graces without even trying. Bewilderment and 'who the heck are you? D:' will work in her favor!