Rumors are spreading that Lindsay Lohan’s new boytoy, British model/reality TV star Calum Best is cheating on the fiery 20-year-old. But why would Calum fool around on the girl he says is the best he’s ever slept with?

A snitch told The People, “[Calum] told me Lindsay’s really insatiable when it comes to sex. [He said] ‘she’s dynamite between the sheets…No girl I’ve ever slept with comes close.’…Calum was knocked out by her body. He said she’s got one of the best he’s ever seen with all the curves in the right places. He joked Lindsay loved being on top during sex and controlling the pace but sometimes he felt he needed ear muffs because she screamed so much during sex.�

The very descriptive source went on: “Calum explained that because Lindsay was so fit he would often find it hard to keep up with her demands. Lindsay likes her sex rough and passionate and Calum says he has the bruises and bumps to prove it. He joked their hotel room would often look like a whirlwind had run through it with sheets torn away from the mattress by the force of their bodies rolling across the bed.�

The reason Best has been so aloof with Lohan may be to keep her on her toes. The insider said, “Calum treats her no different to any other conquest even though she is a big Hollywood star. Lindsay’s used to men doing everything she asks and getting her own way but Calum is the exact opposite.�