আপনি have to build it up: hang out with him/her with his/her বন্ধু and your friends. This will not make the person uncomfortable. When your পরবর্তি to the person, put your foot পরবর্তি to his/hers অথবা আপনি could put your shoulder পরবর্তি to them. If they pull away, don't try it again. The big প্রশ্ন should be asked like this: আপনি should ask him/her face to face-with your and their বন্ধু around. Say it casually, and give him/her a দিন to think it through.
