Pretty good game. Impressive that even after more than 10 years have passed since their first game, Succubus Quest. They are still able to produce such high-quality game. Played through the entire game ,in hard difficulty, for normal ending and true ending.
The true ending is still a bit cryptic and not really explained, so I would like to point out a few things and see if others agree
The true identity of the protagonist is revealed to us that he is named Franz Gildenstarn. Pretty random name...
Hold up... isn't that the name of the demon lord in Succubus Quest? His name was translated as Guildenstern, and I remember his lover was also turned into a succubus. When he was defeated by Lars, his soul was also spilted up into fragments. That demon lord also detests the Succubus, and he is also holding back the succubus invasion into the real world. Either they are the same person, or perhaps just designed too similarly. Interestingly, we see a the same fate befall Lars in the bad end.
Another similar character is the School Nurse. She looks just too similar to Est, the top succubus from Land of Night. There are a bit too many similarity hairstyle, colours, and outfit during battle. Even her unique skill, ubiquitous love, is same as Est, which dispels the Aromasphere(Succubus Academia)/ Incense(Succubus Quest). The skill are the same translation in both games too. Once again, either they are the same person, or just designed similarly. If I remember correctly, her outfit was more similar to the new outfit in Monster Girl Quest Paradox's Collab.
Finally, what is the final fate of the protagonist? Spoiler for true ending