Justin Bieber Dumped By Selena Gomez for 'Stoned Sex Romp' with Sexy Model, Nursing Student Milyn “Mimi” Jenson? [PHOTOS]

So what exactly ticked-off that huge fight between Justin Bieber and Selena Gomez during their "romantic" New Year's Mexico getaway which ultimately resulted in the demise of Jelena? According to recent gossip reports, the "Spring Breakers" starlet decided to dump the Biebs after finding out that he cheated on her with 22-year-old model and nursing student Milyn "Mimi" Jenson... after indulging in some good times with Mary Jane. That's right, shady rumors suggest that the "Boyfriend" crooner partied and smoked weed with rapper pal Lil Twist at his multi-million dollar mansion in Casablancas, CA before "hooking up" with the sexy model sometime back in December. Bieber's reps continue to heatedly deny the raunchy cheating claims.

Hollywood Life reports that the Biebs apparently has a thing for older models - he allegedly hooked up with Victoria's Secret beauty Barbara Palvin AND Jenson... while still dating Gomez.

According to an "inside" source for Star magazine, after a McDonald's drive-thru dinner on December 21, Lil Twist and Milan supposedly picked up Bieber at the Four Seasons Hotel in Beverly Hills. After getting a buzz off of pot and the street cocktail "sizzurp," they then drove to the Biebs' $6 million dollar mansion and partook in some more marijuana smoking. That's supposedly when things got hot and heavy between Bieber and Milan:

"He was really kind and romantic," the source allegedly close to the model explains. "[Jenson] had a huge crush on him [and Bieber] acted like he was [single]... Justin surprised [Mimi] by saying, 'I want to know if you taste good.' He started kissing her cheek and ear and neck and then her whole body."

Woah.

After the intimate hookup, the trio apparently returned to the Four Seasons where the pair started to get into it again. This time, the Biebs refused to kiss Jenson.

"[Jenson] was hurt at the time, but now she believes that he was feeling guilty about cheating on Selena," the insider at Star claims.

So what do Mstarz fans think about the "stoned sex romp" cheating rumors... totally ridiculous, or actually believable?

A rep for the Biebs reached out to Gossip Cop and insists that the shady allegations are definitely not true. Given that Jenson has yet to speak out about her one-night stand with a young Hollywood megastar suggests that the report is most likely fabricated. 

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