If you guys already "act like yr in a relationship" (like you told that other poster)... I think there's certainly a chance that you two could have more than just a sexual relationship together.
What you should NOT do, is sit down at a table and "discuss" it. That's boring, and risky, and demanding.
What you SHOULD do, is take what you already have -- an awesome sexual relationship -- and build on it.
Start looking him in the eyes more when you are fucking.
Start kissing him more.
When he finishes inside you, make sure there is eye contact EVERY time.
Start putting yr hand behind his head and telling him, "I'm yours" when he finishes inside you.
Then, start doing that and pulling his face into yours for a deep kiss while he's still cumming. That way he'll start associating his orgasm and release with your kiss and your devotion.
Then, start adding layers to yr interaction.
When you take him to bed, right before he's inside you, look him deep in the eyes and say, "Make love to me."
Then start throwing out words like that *before* you're in the bed. Start putting them into text messages, and flirting, and just playing around during the day. "I can't wait to make love later." Etc.
Take his hand to take him to bed... "Come fuck yr nasty girl."
Then just start using the word girlFRIEND -- but just slip it in there. Take him by the hand to the bedroom one day and say, "Come fuck yr nasty girlfriend, right now."
That's how you start it.
The secret is, every time you step up the level of "relationship" or "commitment", just do it in the context of hot nasty sex, and he'll LOVE it. Oh yeah he will.
Once you've done all those steps... Get dressed up in some nice lingerie, take some selfies, and send him one, with a message like, "Baby I need you to come slam yr commitment deep inside me... nice and hard" -- and you'll have yourself a boyfriend who suddenly finds the idea of commitment awfully sexy.
Just do it in baby steps.
Same ideas have kept my marriage hot for 15+ years. (oh and lemme tell you just how hot you can make the idea of marriage... oohh gurrrllll ::wipes brow::)