Well, the reason could be many, including the fact that she has been locked inside a house with the same people for about 40 days, and not having access to many things that may help keep one"s sanity, such passion is bound to take shape and help boost morale of some people at least.
And what about privacy? It is obvious that the two passionate loving souls, while sharing their two-minute-long kiss and fondling each other"s bodies, were completely aware that their romantic encounter is being fully captured on camera. And their decision to go for it even then, is nothing but courageous.
But when are we going to see this passionate encounter? Probably never, or at least not on screen of our television. The encounter certainly has some adult content and cannot be aired on prime time television in India!