User blog comment:PercyJackson17665/What role Julie gets if Ben marries Kai Green in future?/@comment-1399043-20120818131055

Kai as Ben's Wife and Kenny Tennyson, exist in a parallel timeline as seen when a different Ben 10,000 appeared in UA and from the way he talked, it didnt seem that he was married at all (and Kai hasn't been seen since Ben was 10, and hes in a serious relationship with Julie.)

I doubt Ben even still holds any feelings about Kai so it is very doubtful that he would marry her during the current standing of the events as Ben has yet again changed his future (as if im not mistaken the UA Ben 10,000 is no longer his future since he has the new Omnimatrix that doesn't have the ultimate feature)

So all this "Kai should be his wife and Julie is ugly" is pointless, unless the writers have him dump Julie and have Kai come back and her and Ben becoming an item, might as well close this discussion since its not up to the fans.