Need some advice/help

Hi I'm 21 and currently in college. Recently I've been seeing this guy who's much older than me, he's in his late 30s. We met on Grindr about a month ago, and when we first met, I didn't expect to see him again, but he was so sweet and accommodating. Ever since we've met up at least once a week. I really like him, but a few things bother me about him. He's told me that he's been in a 8 year open relationship with this guy and is still possibly in it? I'm not quite sure because he said things weren't working out so well between them. And he's talked a lot about hooking up with guys and going to orgies. I don't mind if he does go to orgies or crazy sex parties, but it worries me because I'm looking for something more monogamous. I know he hasn't been seeing anyone else after meeting me, but I feel like he might get bored and have an urge to seek out those sexual thrills. I'm also worried about being younger and naive I guess. I just don't know if I'm making the right decision choosing to be with this guy in the long run.