I don't know why some people felt like the (implied) suicide came out of nowhere. I won't say I wasn't surprised, but Tomo committing suicide seems to me a very plausible, reasonable development. I mean, did she seem happy to anyone else? Looking for a purpose, unable to get close to anyone, tinges of (somewhat justified) self-hatred, overthinker, unhealthy habits . . . seems like a classic candidate for suicide, actually.
And at the same time, I can see why someone might get obsessed by her. The cool self-reliance, the almost unconscious style, the clearly impressive intellect . . . in many ways, objectively she's a horrible person, but there's this strong "What if?" that says there's an amazing person there if only she'd stop stifling it, if only she could be saved from the shit (much of it self-inflicted) that's crippling her . . . people do get obsessed with that kind of person. So it's kind of realistic.
Overall, although this was both a sad and depressing story, I thought it was very well done and I didn't find it repugnant. This is a good one. Unlike (spits on ground ritually) "The feelings we all must endure" which I did find repugnant, and which I actually thought had some serious flaws in execution as well.
I must say Amano Shuninta is, if nothing else, an exciting writer. You never know if you're going to get happy or sad, cynical or relatively pure, and it's hard to even be sure if quality-wise you're going to get excellent or crap. But that does mean that when you start reading one of her works you can't readily predict what's going to happen.