A nog almost certainly tried to rob me about 2 hours ago I was on the subway and I exiting the turnstiles and coming out of subway station. The part of the subway station I was using has two stairways out in the street about 50 feet apart that both lead down to the subway. Between them is the elevator. Whichever stair you choose to take, as you pass the landing level and go down into the station, you can make eye contact with the other stairwell as they are then parallel to each other. As I am coming out of the turnstiles and making my way 30 feet toward the stairs closest to the turnstiles, I see a young nignog coming down the other far set of stairs. Instead of proceeding to the turnstiles, he now turns towards my stairs and starts walking up them diagonally behind me. He was casually closing the gap between us. When I get to the center of the first stairwell heading up to the street, I stop deliberately. When I do that, he is basically standing to the side of me and says to me kind of curtly: "I'm not going to rob you." I told him: "You're coming up behind me from the other set of stairs" (no logical reason to be doing this) and I flicked out my knife towards his face and told him "I’d have to do what I have to do." He then made some snide comments that I couldn't really hear (but basically trying to be dismissive) as he proceeded in front of me several steps and out of the train station. He went one way and I went another. He brought up robbery-not me. Even if he alleged to have forgot something and was going back out of the subway to retrieve it, there is no reason for him to come across to my side--they both lead to the street. He made a concerted effort to be behind me. He came halfway down 1 flight of stairs, crossed over and walked up mine. No one there but me.