He was flirting with my girlfriend. Anyway, I saw his name in her phone and I simply text him and politely asked him to not flirt with my girlfriend, especially in front of me, he text me back saying he was gonna beat my ass. Then today I saw him from far away when I was outside, but took no notice of him and just got on with what I was doing, it seems as though he wants to fight me. I have been told that he thinks he's a badass and is "hench", I'm clearly much bigger then him even though he's older then me(me 15, him 17), but I don't like fighting as I'm a calm and collected person. Me: 6'1" 180lbs Him: 5'7" 135 at the most What should I do?