I hav this this strong feeling dat he is sum kind of a undercover agent or cop ..
I think the reason dat he is asking Sups to get close to Dutta to gain his trust is to collect sum proof against him ...other wise which man in his right mind would ask his girlfrnd to get close with another man ....& Sups & her father is also aware of this ....& this also explains Sups scared bhaviour ...!