SPOILER
The order of the game is as follows:
Chapter 1 - Noelle breaks up with her boyfriend (needs a Saturday when Sarah is away)
Chapter 2 - Noelle flashes you her knickers (when you keep talking platonically to her)
Chapter 3 - Noelle shows you her bra (when you keep talking sexy to her)
Chapter 4 - You spy through her keyhole and see her masturbating (at 11 pm any night; when you're standing on the first floor you get a hint that you hear a groan)
Chapter 5 - Noelle flashes you her tits in the kitchen (it usually happens after you help her prepare the mid-day meal. She will also do it if you use the snack ("grignoter") option if you're alone in the kitchen.
After this scene you get the hint "To encourage her to go further can be a gift please her". The gift is the lingerie, so don't give it to her until after you've triggered this scene.
And this is the point where I got completely stuck. I played on for weeks of game time (and nearly as much real time!) but I couldn't get any further scenes with Noelle to trigger.
Eventually, when re-playing from an old save point I realised that after the Chapter 5 scene in the kitchen the scene where Noelle and her boyfriend split up is replayed. I thought that this was a glitch in the game so I ignored it. Finally, when I had tried everything I could think of I decided to try talking platonically to her again, and the photo where she flashes her knickers re-appeared. I talked sexy to her a couple of times and she flashed her bra again. And the next time I was on the first floor at 11pm, I could hear groans coming from Noelle's room again. I looked through the keyhole again and saw her masturbating, then when I knocked on the door she answered wearing her lingerie (you might have to repeat this a couple of times, looking though the keyhole and then knocking on the door until she answers in her lingerie).
Go into her room and examine her. From now on, every time you knock on her door she should answer it in her lingerie. The next day knock on her door, go in and examine her again and the next time you go back into your bedroom and Sarah isn't there, Noelle should be. You'll then get the scene where she strips off her lingerie completely (Chapter 6).
Very shortly after this you'll get a text from Noelle asking you to join her in the garden; when you get there you'll also have the scene where she strips off her bikini.
(The first time I did this was on a Saturday night when Sarah was away, which meant that when I went back to my room (at 11pm) the lingerie stripping scene triggered straight away, which took the time to midnight, then I got the text to join her in the garden which took the time up until 1am; the game didn't seem to like this at all, and was very glitchy until it went back to normal the next Monday morning.)
I think (it seemed to work for me) that you peak through her keyhole, wait until she answers her door in her lingerie, if at that point if you don't actually enter her room but instead go back to your bedroom and go to sleep, if you knock on her door the next morning she'll still answer in her lingerie. If at that point you go in to her room and examine her, the next time you enter your bedroom and Sarah isn't in it, Noelle will be there and will strip, closely followed by her stripping from her bikini in the garden. Doing this in the morning prevents problems with the game going beyond 11pm.
From then on you should be able to carry on and unlock the rest of the Noelle scenes (she asks to borrow 1000 money off you, after that you get Chapter 7, where she masturbates using a vibrator in the kitchen), and then Chapter 8 where she gives you a hand-job in your bedroom (the hint for his is that you need to do more domestic tasks; I found that if I mowed the lawn and cleared the pool a couple times at times when she was also either on the lawn or by the pool (i.e. she could watch me doing it) once I went back to my bedroom to read a book she eventually joined me).
Or, to put it another way, once you trigger the scene for Chapter 5 the game resets itself to Chapter 1. You have to play through Chapters 2, 3 and 4 again, after which you can go on to Chapter 6 (Chapter 5 doesn't seem to replay itself).
Anyway, I hope that makes sense. Like I said, I don't know if it's the correct solution, or if it will work for everybody, but it has worked for me.
Another thing I've found, once Noelle's attraction to you is high enough if you keep sending her sex texts eventually she'll respond with one of her naked pussy, I don't think anyone else on the thread has mentioned this?
