DESPERATE Darnell had one last crack at Aussie babe Sara last night, as the pair whispered and held hands under the blankets.

The couple's rollercoaster relationship soared to another level as flirty Sara dove under the covers with the Albino rapper while sitting on the couch, and then draped her legs over him.

Click here to see more of Sara and Darnell's cavorting ...

Even Rex's teasing couldn't separate the couple, with Sara saying: "Let's see how long we can stay under here."

Delighted Darnell - who appeared to have forgotten about the "amazing" girl waiting for him on the outside - replied: "It's getting hot."

Rex told his buddy not to get his hopes up, warning him that Sara would be flirting with other men in front of him as soon as they left the BB house.

Darnell fired up just at the thought of it.

"You know me, that could cause disaster 'cause I get mad...I'm a jealous person dude," he said.

Get ready for fireworks!