I’d Rather Tell The Truth?

I’m 18 years old and currently living with my parents. There’s a person that I’m regularly sleeping with and I’m kind of tired of having to come home the same night, I’d much rather just sleep over and go to school from their house the next day. My parents know that I’m dating different people, but the person I’m actually sleeping with isn’t serious enough for me to introduce to my parents.
I could lie and say that I’m staying over at a friend’s place, but I’m not a big fan of lying. It’s not like my parents can stop me from spending the night, but I don’t want them to feel as if they have this out of control daughter that doesn’t listen to them. They know I’m gay, so the fact that I can’t get pregnant does help to soften the blow. Even though I’ve never brought up the subject, I know their main concern in me staying over is that they don’t want it to affect my schoolwork, that the person in question will pressure me into things I don’t want to do, and also that I’m having sex with someone I’ve only been on a couple dates with. What would be the best way for me to tell my parents that I won’t be coming home for the night, and still have them feel like they have parental control?
Also, there’s no way for them to know how well I’m doing in college because there aren’t any report cards or written tests.