I reread this today. I once really liked this story because it features a strong trans female character whom I can identify with at times being a trans woman myself. However, rereading it makes me reconsider that regard for the series. While arguably not at fault because the one violating his relationship was the boss whom had the affair with her, it's still really bad optics and she was really just living an emotionally-distant lie in public. Not to mention the second she's outed she disappears because unless she's personally involved, she doesn't give a fuck.
Kashiwa, I can really empathize with. However her relationship with Kasumi isn't healthy. Kasumi basically sees her as guy she can dress up as a sex doll half the time. Even after everything, she still treats everything about Kashiwa like she's just like any guy. However I can understand the difference between disappearing to be yourself and disappearing like Botan did. In the end, she stepped up to support her younger sisters.
Sakura is way too tsun and lets everyone walk over her half of the time and the other half she's acting weirdly. At least she becomes more reliable at the end. However I hate how that reliability seems to coincide with that het relationship of hers.
Momiji is the best character by far. She's smart, caring, and has a level head. Honestly I don't like the whole triangle they set her up with the "moe piglet" and her best friend. He's ignorant but he tries. Her best friend is much better. We can hope with her love of gay that she ends up in a yuri relationship herself.
Anyway, based on these characters, I've created a chart: