Ienzo...?

[zexyishsmexy]

because Roxas was the youngest of course

mmmmhmm, and if it IS true that Zexion is the second youngest, my theory is basically proved. Because Demyx is school aged, and older than zexion, but Roxas is younger, so he's somewhere between 14-18. Right?

 

[Haxon]

Im having trouble finding the interview, but hopefully there is other people who have read it that can back me up while I search.

 

[DiceKiller]

My study of the “darkness of the heart” began with a simple psychological test and quickly snowballed. Spurred on by my youngest apprentice, Ienzo, I constructed a massive laboratory in the basement of my castle. Unbeknownst to me, my six apprentices began collecting a large number of subjects on which to perform dangerous experiments into the “darkness of the heart.”

This was the only info I could find. Not sure if it helps much. :/ If he was the youngest, then he really couldn't have jumped a bunch of years in a one year span. So much must have been the youngest nobody when he joined. But by the time Roxas joins....