Interesting game. I'm looking forward to what this could become. You might already be aware of some these points but here goes: Sometimes your party members will get stuck at the door, or freeze at when descending or ascending, while still taking up space as party members. Other than fixing that bug, a more convenient way of managing your party would be a great addition, like a dedicated menu for it.
What direction are you planning on taking this game? Rogue-like or more open exploration for example? Depending on that, I think a save option would be great to allow you to explore and try out things for fun without losing stats, etc. like getting caught on purpose.
I know this is early development, but a little something to tell the player that they have completed everything would be appreciated. I made it to the final floor, 10, cleared it, and wondered around, looking for a message, finish line, just something that would say “congratz, stage cleared” “you have reached the end of the current game” some like that.
I like the different temperament of the characters, PC and NPC alike – the tooltips were helpful in guiding me to know what sort of non-combat action would be best. So far, it is lacking, but with some actual dialog, events etc. a lot of fun could be had with it. When an NPC comes with a request involving bindings, having something more happing after the restraints had been applied, would make it NPC request something to excited about. Especially for the sub route. I think it could be a lot of fun messing around with the various temperament and requests of the NPC. So far, I think there is most to do as a dominant, while the sub route was rather uninteresting. The sub route needs the option to surrender (that could also be a way of gained favour with sudden temperament) and some more captor to captive interaction, just to name some examples.
As others have pointed out, the game is really easy once you have figured it out: Capture someone within your “power level”, drain them for all their stats, move onto a new one, repeat until your stats are maxed, and find someone strong you can recruit. This system needs to be fleshed out to avoid repetitiveness.
A little tutorial would be nice. By reading the guide and testing things out, I did get a hang of it, but a little guidance at the start would shorten the time it takes to go over the mechanics and might prevent pushing those players who struggles to understand the gameplay away.
The info screen blocks view of the text indicating your target while your turn is ready. I accidently used a skill on the wrong target because of that once.