i think that all this is mukti's plan (drink, neckalce..).. because of the way ud treated her.. and how prerna didnt listen to her.. this was probaly the only way to show that something had happened to her.. and she could punish ud.. it doesnt matter if they did it before since no one is going to beleive that.. just making this can get mukti revenge..
i hope i explained good enough for everyone to understand..
please reply back as soon as possible as i am waiting to get replies
-harjot