telling parents you want to start sleeping over

So I'm 19, turning 20 in early November, and I'm in a very serious and committed relationship with my boyfriend. My parents love my boyfriend a lot and it's seriously the first time they've ever admired anybody like this. So he's getting his own place and we've talked about me staying the night there. We really want to spend some nights together but we're afraid to mention it to my parents because I'm scared they'll dislike him for it. What should I do? No I don't have a job
But it's because I was working a full time job and going to school full time and I was paying for school through a loan. My parents made a deal with me that if i quit my job, they'd pay for school and they'd support me. Anywho, one time I was talking to my older brother about it, who's had sleepovers with girls since he was 17 and he said I need to be an adult and just say hey I know I live with you but I'm going to stay at his house sometimes because I want to and I'm an adult. Lol so any advice?