Why does the same guy keep coming back??

Backstory: in highschool (5 years ago) this guy broke up with his gf and started talking to me. We talked for a couple months then he ended up getting back with his ex giving me the excuse that he was leaving for college. He left for college and kept in touch and continued to talk to me and hangout and hookup (while still with his ex). They ended up breaking up and he started dating a new girl. Same thing, he would talk to me and cheated on that girl w me. So both of his serious, long- term relationships he’s cheated on w me. Now he’s single and he’s talking to me again wanting to hangout. I’ve asked why he always comes back to me and his reply is that ‘I’m cool and fun to hang out with and be around’.

What does this mean? Does he have something for me or is he really only wanting to hangout to hookup? But why does he want to continue to hook up w me for 5+ years now?