Credit: Brandon Todd/Splash Photo: Leah Messer & Corey Simms

In a shocking display of baby-daddy douchebaggery, Teen Mom 2's Leah Messer's ex-husband Corey Simms has been spotted macking on other Teen Mom stars! That's low, even for MTV reality stars.

Leah and Corey got married after a painful breakup and we all hoped the best for this hot mama and her twins' daddy. Of course, that was foolish of us, because they divorced six months later (although, based on the camo vests the groomsmen wore, bullet dodged, as far as we're concerned).

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First he tried hitting on fellow Teen Mom star Jenelle Evans (whom we've nicknamed "the Lindsay Lohan of the Teen Mom bunch"). Uh, minor detail? Jenelle and Leah have become really good friends through the Teen Mom series.

"She was shocked he would hit on her," a friend of Leah’s says of Jenelle, "and she immediately told Leah."

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So, obviously, he moved on to 16 and Pregnant star Nikkole Paulun, whom he's reportedly been "hooking up" with. She came to see him in West Virginia, and Corey even packed up the twins Aleeah and Aliannah and took them on a trip to the Columbus Zoo in Ohio with Nikkole. Like, as a date.

"Leah was livid when she discovered that Corey took their twins to the zoo with Nikkole as his date," a source dished. Well duh!

Ugh, serious dating faux pas, Corey. Back away from the reality franchise. Maybe date a girl without a kid? Who knows!

Source: HollyBaby