What do I do?

I've been in a relationship with my boyfriend for a little over two years now, and we've been doing long distance (both our families don't know we're dating, so it's a complicated situation) for a little over 1 year. He lives in India and I live in the states; we met at school when I moved to India, and we are still together even since I've moved back to the states. We both love each other very much, and are very happy in our relationship, but he is a bit protective of me and just wants to make sure I'm safe since he's not here with me. I recently added a guy who was in my school on instagram. We just chatted as friends as first but then it quickly turned into him constantly commenting on how hot I was and how he wanted me to send him nudes despite repeatedly telling him that I'm in a relationship. I eventually blocked him on instagram and Facebook, but he keeps making different accounts and messaging me. I want to tell my boyfriend, but I'm afraid he'll get super pissed off and actually go and beat the guy up. I don't want this guy to keep messaging me, but at the same time I don't want to put my boyfriend's safety at risk and get him in major trouble... what do I do?!?