Why would he act this way towards me? I'm his fake girlfriend?

The other day he told my friends that I was his girlfriend ( but I'm not ). So, he just told me to go along with this "pretend play". He was my friend and now he wants me to act like I'm his fake girlfriend. We both started eating and drinking out of the same cup/food. But I notice that he does that to his other "girl" friends too. But she've known him for quite a while, so I know they're just sharing food because they're really close. Sometimes he would call me a "stalker" just cause we see each other a lot around school.

So what could this possibly mean ? Nothing ? Does he like me ? Does he like one of my friends?