Managed to beat this, got the bad ending. As others said, used Sugoi Toolkit with the VN OCR Tool, works as well as you can hope. I really don't think its that bad, the scenes are pretty hot, some good seduction fetish content. I particularly love armpit/smell/foot/kiss play, so Sekhi is always a dub in my book.
But zero reason for it to be a game. Just let it be a VN.
Also can't be assed to run through all the mazes again to see the good end. Personally,
The last room was definitely the best though and worth spending the most time on. I really ran through all the mazes, its not worth dealing with game overs, and the game seems generous with throwing those scenes in the rememberance room to enjoy without punishment later anyhow (that, or I did enough with my post-game save editing to see them all? dunno).
Anyway, if someone figures out the good ending, I'd be interested if its in the same room. I couldn't figure out how to cheat it unlocked. But certainly worth a playthrough for those who enjoy the genre (rNTR with lovey-dovey femdom). I particularly liked the last succubus sister who is very clearly supposed to just look like the MC's partner but super busty. Was a fun trope and I'd love to see it more in h-games.