Though sid keeps making it look like he's on her side.. he is actually with paras n mahira.
I think sid feels pahira wont do palti like sana n asim.. but sid seems to have forgotten that's how paras has entered the shukla gang.. by doing a palti from there.
The way sid manipulates her into listening to her is awesome.. he tells what he wants to paras and makes sana agree.
Same method used by paras earlier to enter sid gang. He used sana cos sid used to listen to her.
Unfortunately for her it backfired cos sid started listening to paras.