There is no nightwear option in sex, and the time of day doesn't effect sex. Pictures would help.
I mean the "Default" option, she was already wearing her nightwear aka panties or essentially nuffing.
Before trying again I wanted to buy all the remaining outfits to check it more thoroughly. But this took a while. Several events happened which took my freedom, Hana, Cornwall, Ashley+Fairies, Kate, and a few others. I bought everything but could not pick it up because of weekend.
After that it got only weirder.
I tried a night-visit with succubus. And it worked!? The first ever. She mentioned Hana before, could that be a difference?
I could do a photoshoot with Lingerie after I bought it but before I picked it up. But I could not chose any of other outfit which were waiting for delivery.
Finally I could pick it up and start to give her stuff. When I gave her the slut-outfit the talking scene was okay, but the sex happened with succubus outfit!? Maybe because I did chose succubus a few nights before?
Another night-visit. Everything worked!? (Except for Lingerie which I was still in my pocket.)
After a couple of more Hana and Fairy events I finally could give her the lingerie. Okay let's try it out immediately (at noon). Guess what happened? Slut-outfit!
Okay, another night-visit, Default, Bunny, Succubus worked, everything else led to Slut. (okay that means Slut worked too)
Update, not sure if this intended or also some weird effect:
When Maria enters my room in the morning she wears the succubus outfit but the subsequent sex happens nude.
Dunno if this is important, In this game I haven't used the "change outfit" option for any girl so far.