After Buffy finds out about Xander's lie about what Willow said about Angel, she curses him so that he would never experience love. But as ususal magic didn't work right on Xander so instead of never knowing love Xander is curse to never grow old until he finds his true love.

Xander is forced to watch those he care for grow up, have a life and finally die as he remains the same age as he was when Buffy cursed him. Any wounds he recieves to his body is healed almost immediately but no magic could heal the wounds to his heart and soul, so after a time Xander closed his heart to everyone expect to children.

As mankind left the Earth to explore the universe so did Xander. He made it a habit to drift from planet to planet to keep people from noticing that he never aged.

Having settled on a new planet, Xander once again started his life when they arrived. After being captured by the Necromonger, Xander is dragged before their leader.