What you are missing is the threesome between the two after you've progressed further enough with their respective questlines. You get a hint that there's something you can do them both when you talk to them on a certain day of the week. Don't remember which. The others become available once you initiate the Easter Event.
The other two Brittany scenes you're missing come from her doing Yoga and doing the Babysitter for Friday a second time. Hope it helps.
Yes, I think there's only one scene that could be repeated, but I'm not sure. It's with a condom (how boring), but it was his first time, so he completely broke her pussy.
You have to go to the apartments where Molly lives at night, then to the gym at night (always the outside area), then I think you have to talk to Lilly at night in the abandoned house. And then the game guides you on its own.
The newspaper has to be in the living room or in the area in front of the living room where the mirror is (I don't know what you call that). Well, you have to read it, I don't know, in the morning or in the afternoon. Try different times. Then you go to Molly's house and to the gym at night.
Buy lockpicks at the Bookstore, then on second level of school picklock the lockers.
