Yes... Where the magic potion made Kai sexy, the magic potion only gave Rei a moustache =(
Poor, poor Rei...
... Too bad the magic potion didn't give him a personality. That would've been better. (Sorry to all you Rei fans out there! XD)
(Pstt, I drew that moustache myself *teehee* I have no idea why I'm so proud of it, though! LMAO! I'm mad =P)