He flirts with other girls.. How do I get him to stop?

My BF has a lot of friends that are girls. Most of them which have a crush on him(I don't blame them he's charming asf 😂). But like we aren't in the same class but when I do see him he's always talking to them and flirting with them. And I feel as though he texts them a lot I know he texts a couple of them but I don't know if they are friendly texts or flirting texts. How can I tell him to stop, without creating a drama? Thanks for you help guys 😘😘