This is low, even for serial-cheater Tristan Thompson. Khloé Kardashian has always been the Cleveland Cavaliers baller's biggest fan, until she learned that he cheated on her with multiple women just one day before giving birth to their first child True Thompson. Now that the Cavs are in the NBA playoffs, we're sure she would have been screaming from the sidelines decked out in maroon and gold, but now a source tells In Touch exclusively that his mistress Lani Blair will be there in her place.

"Khloé told him she isn’t going to any of his playoff games in Cleveland and gave him back his four box seat tickets," the insider explained. "So Tristan gave the tickets to his sidepiece Lani!" Um, seriously? Tristan was clearly pretty careless when it came to cheating on Khloé with Lani, and there were even hints on Lani's Instagram that something was going on, but this is a whole new level of disrespect. And guess what? Tristan doesn't give an eff.

"He’s crazy, crazy about Lani and isn’t trying to hide her," the source continued. "Lani’s been asking to come to his games to cheer him on for the longest time but Tristan always wanted to keep her in the background, until now. Khloé has no idea that Tristan did this and it seems like Tristan doesn’t care about her knowing either."

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The Cavaliers are beginning the second round of the NBA playoffs against the Raptors on May 1, an the game will take place in Cleveland, where Khloé is still staying after giving birth less than a month ago. We can't imagine how miserable she must be, forced to stay away from her family in a city where she doesn't know anyone, and then to find out her scumbag baby daddy gave her tickets to his sidechick while she's at home taking care of the baby. It's just disgusting.

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