Guy continues to look at me as I go down the escalator?

I just want to know what you guys think of this guy ( I will explain.. like now) and what he was thinking of me? So, I was looking at this guy and then he saw me looking at him then looked away and then looked back at me ( but I quickly looked away and put my head down, I looked at my shoes) and then I just got onto the escalator and I saw him still looking at me and he was smiling ( like something was funny) . I think he kind of looked me up and down, and then he looked at my face , and did this weird thing like he looked me in the eyes and then looked at my lips quickly and then just continued to look at my face ( I wasn't looking at him , but I got the sense he was looking in my direction). And then when I was at the bottom of the escalator ( out of his vision) , he turned his head to continue looking at me? What was he trying to do?
Guy continues to look at me as I go down the escalator?
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