How to convince my parents to let me go to a concert with a guy?

Okay so this guy invited me to a concert and i really want to go but i
dont how to ask my parents. this guy isnt my boyfriend, but we flirt
and stuff. but it wont just be me and him, a bunch of people are
going, including my best friend. i dont want them to think this guy is
my boyfriend or anything, so what should i tell them and how can i
convince them to let me go?