Ok basically I’ve been casually seeing this guy. But that I mean we slept together 3

Times. I’m 20 and his 25. We both live with our parents it’s no big deal because where I live in Australia it’s common also I do pay rent. Anywayyy I really want to spend the night at his, he has told me I can. But I don’t know what to say to my mum I’ve never slept at a guys place even when I was with my boyf. When I was with him I asked and it was fine if I went to his but not for him to come to mine I understand that. But what can I say to her this time because she doesn’t know the guy and it’s purely for sex. I know it’s weird that I have to “ask” but my mum and I have a really good relationship and she knows most things that go on but I really don’t want to lie to her and I feel a bit awkward asking. Because it’s kind of out of my character.