I think I've enabled piss (17; turn on I think), but even while working as a toilet boy I didn't see any scenes. Perhaps I need DLC, but to install it I have to start the game from the scratch and I don't have any desire to grind all these scenes again; tbh I'm already getting bored, so I went to see some MGs, got the Panty Key, but the fights in the tunnel got really repetitive (I've finally lost to 4 kitsunes); I guess it's time to cheat for stats, cause the game's getting too slow for me. While working as a toilet boy I had 3 scenes with skullgirls during one job, that's a little bit too many for my taste.
The codes should work without restarting the game. The DLC is defunct for a good while now, for several updates only the codes method worked. I never tried enabling only 17, so maybe that is an issue? I don't know. I will know more when the update comes out and I will have to deal with it again.
The game has repetitive elements yes, unfortunately, but I don't think at the level most devs can code its even reasonable to expect a fully non-repetitive sequence of scenarios in games which rely on mechanics to generate scenes such as this game. I think that would be a monumental effort even for a genius coder.
As of now only visual novels [or rpgms mixed with VN], where each scene is manually added can avoid that. Full random generation would be cool, as in random in every way [not just chars but actions too]. I wish I was a programmer, because then I would aim to create a mechanism whereas I would try to treat some simple actions as invariables and then formulate a logical way of them to combine randomly. Lets say I would define as main "objects" as many fetishes and positions as possible and each fetish having at least 20 variations within, so that in-game you'd experience them in unexpected combos, both in terms of what is done to you, as well as by whom, how many and where. But since I am not a programmer, I can only fantasize about such things, and in the meantime I am grateful for whatever I can get.