nOW this is what i think,,,it could either be 2. Nakul or 3. the retarded guy that KT always helps out. why nakul....think about it,, he does what ever his mom tells him to do! and we all know that the mother hates KT and she doesn't want KT to marry Luxsh. so she probably made the plan for nukul to rape KT so that the marrage could be stopped. If the mental guy raped KT then it would also make sense since he could have a thing for KT and wanted her for her unconditional support. But I dare say, One thing I learned from EKTA drama's is that she could take a really good character and make them bad,,,so here it is ,,i also think it could've been LUXSH himself,,,maybe the mother had planted a hate seed within his heart just like what she did with nakul and wants to destroy anything that is conected to ganga and tulsi or in the way of their wealth..may im compleatly wrong but who knows........and i also remember that from the rape scene the head of the rapist resembled the shape of luxsh's haircut.........what do u guys think?