Courtenay Semel recently lit Casey Johnson's hair on fire.

In Semel's defense, her ex-girlfriend did have the nerve to show up at her house.

According to Page Six, Johnson got into a fight with her current partner earlier this week. Seeking comfort and/or cunnilingus, she headed over to Courtenay's. Big mistake.

"Casey went to Courtenay's house, and Courtenay proceeded to beat the crap out of her, and then she lit her hair on fire. Casey had to be hospitalized," a source told The New York Post.

Semel didn't deny the disagreement, though she referred to the whole hair-lighting accusation as "a major exaggeration."

Not worry, though: all is well in the land of attention-hungry lesbians.

"Courtenay and Casey are still close and are heading up to Sundance for the weekend," another source said, while Semel's rep added that his client's on-again, off-again relationship with Tila Tequila has ended.

Sounds like Courtenay and Casey may be in for a scorching hot time in Utah this weekend. Get it?!?