For a long time I could not find 3 and 6 scenes in the game, so I give a guide to people with the same problem. These scenes are located immediately after the last battle in Yalen, (do not choose "Skip Yalen", choose "Skip prologues") after it you are given to go to any tent, you need to immediately head to Nadine. After a short dialogue you will be given the choice "Let her relieve you" or "Go back to your tent", depending on which option you choose, the third and sixth scenes will open. If you do not have any scene open, you can ask me, I have all the scenes.
(thx google translate)
Viewing post in Shuggerlain (v0.73) comments
the second sex battle can be found by chance in the forest. When you're at camp, click "Take a walk trough the camp's surroundings"
I think the chance is about 10%. If you can't find it for a long time, then try to do it in another chapter.
The seventh scene is on the first date with Saraith (I don't know how you might not find it). For the only choice on a date, choose "Move her slowly away by her shoulders"