Why does this guy friends watch me?

There is a guy who likes me well we both make eye contact and his eyes dilate, he looks at me and smiles and alot he bites his lips. One me and him made eye contact and he held it, then his friend t

turned around and smiled. But he has never talked to me before, not shy outgoing and talks to other girls and guys. Like everyday his friends watch me and follow me around, like their keeping an eye on me.

Like today me and my friend were sitting outside on the bench, then his friends came out but he wasn't there he was getting ready for a football match but anyway his friend keep looking over at me then they were talking and smiling, and then me and my friend got up and was going in side then they moved away and I saw them heading down to the changing rooms to tell him probably

Like when he is not there why does his friends keep watch of me or look over and when I was going they moved?