She first showed up in the comic when Hector's friends went shopping at the mall. He cheerfully introduced himself and was lectured by her for not acting "dark" enough. But Hector didn't completely blow it, for when they went to their favorite goth-style store, he picked up a shirt with a message that made her swoon at Hector's good taste: "You laugh at me because I'm different, I laugh at you because you're all the same". All of them proceeded to buy and proudly brandish this awesome, unique statement.
Xandria likes Hector, so she invited him out on a date. When it turned sour, she revealed that she'd had a history of bad boyfriends. However, gifts won Hector a place in her good graces again.
She didn't believe Hector when he told her he was a werewolf, thinking that he was simply talking about what he wanted to RP next. But Hector eventually convinced her when he finally got her to help tie him down for the next full moon...
It's also implied that she sorta has a thing for Hector's brother Victor since she was eyeing him when she first met him.