Sounds like a trademark to me, and when it is given to a real person his parents have trademarked their child with a unique name creation.
The thing looks like a portmanteau of
Alexander and
Xanthos (or even
Xanthia) with the fancy ending -ian. And Xantiana is also sometimes used as a given name (see
https://www.behindthename.com/name/xantiana/submitted ).