It should autosave as far as I know. you can unlock lewd scenes atm with buying the Nile or the Sammy plushy, and surviving a night with it on your desk. You can also complete the minigame for a Poppi preview!
i got 2 plush but i dont know how to use it on my desk! + how i can change the pigg plush with another? cause i buy a few and i dont know how to change it! sorry for many questions but can u tell me a few tips cause i dont know! btw amazing game
You can change it at the end of a night when you are at the store. There is a button to customize your desk (bottom left). Hover the mouse around where the pig sits until you get the name, then click. It should change to another plush toy.