Hi, bought and played the game on Steam and damn if it isn't an awesome game! Love it so far.
Some questions though, how many of the scenes or which content are permanently missable? And are scenes universally unlocked across saves, or are they just unlocked based on the current save?
Scenes aren't shared through saves. There is no plans for permanently locked scenes. You can miss a "romance" interaction with some characters, but all NSFW content can be recoverable by other means not yet included in the game. But I'll try to include it in the next patch. So if you missed a scene at the moment, you'll be able to recover it later.