Bingo!
1. My looks are in the eyes of the beholder.
Spekkio's appearance changes depending on the party's level.
2. Of course, I never look any better than the very first time.
His first form is a Kiwalla, which is about as cute as Spekkio will ever get. His appearance just generally goes downhill from there.
3. But then, why worry about looks when you're saddled with godlike defense?
Spekkio is essentially physically immune.
4. On the other hand, I teach to you the very tool you need to beat me.
On the other hand, he's not immune to magic and he teaches you how to use it.
5. Not before you run across the room clockwise three times! I'm easily entertained, I guess.
The pointless "run across the room clockwise three times" gimmick, of course. I'd give up if you people didn't guess it from this clue. >_>
Anyhow, ball's in your court, Ultra.