*POSSIBLES SPOILERS*
In several of my previous games, I had ideas for some design or scenes that perhaps didn't quite fit the tone (either erotic or gore). So I just avoided those parts a bit. Now, more or less, I know how to do that kind of "censorship" as an optional thing, I hope it will give me more creative freedom in the future. I also didn't expect anyone to use the screenshot function. In fact, I don't even remember it exists. So I never actually tested it, haha. :P
I realized that many of my endings are always very tragic or pessimistic. That's why I wanted to do something more "nice" this time, or pleasant. Although in Sumire's case, I don't know whether to consider it a bad or a good ending. I originally wanted to add more endings to each character, and make a route for Manami too. As well as being able to search for more items to unlock interactions, secret routes, and even some extra characters. But, it was starting to be too much work for me, at a time when I couldn't dedicate so much time to this.
The reason why Seiichi doesn't show his eyes, is to represent that he is traumatized and hurt, as you say, because he probably won't stop crying. (Regardless of the ending in Reiko). Originally, Lirius was to be an additional character. In fact, I think I left her sprite as a character (both censored and uncensored) in the files. She was supposed to be a monster that you could kill to advance in the cave, or with whom you could dialogue, depending on the items you had. This is something I discarded in order to shorten the length of the development a little more.
Someone told me that he had a Ren'py error with Rebeca as well. In fact, she can intentionally throw a Ren'py crash. It's not a bug, as it's actually a simple picture. In all my testing, though, I've never had a crash or bug in that regard, so if it's not the picture I programmed, it could be something that never happened to me, or the will of Rebeca herself. (Which would be perfect). 🎀
Thank you very much for your comment and feedback. I'm always happy when someone shares their experience and thoughts about my games. I know they're not perfect, but still, I hope you had a nice time with them! Thank you so much. :)