Really cool game. The writing is fantastic, and there's so much of it! Everyone's all distinct, the plots are varied and interesting in their own way, and the nonverbal choice system is just awesome. Shoutouts to the way Cirno speaks, it's so goshdang cartoony. I have no idea how her "accent" would actually sound, but through text alone she's got tons of bombastic energy.
Music-- yay! It's tami, and wow, I could barely recognize her stuff. This soundtrack felt incredibly different from the work she did for the Kotohime games. A lot bouncier and more cartoony. Though, maybe you could've done a slower track or two, or placed them differently? Some songs seem oddly upbeat during serious moments. Don't worry though, it's still a 5/5 to me.
Great sprites, and there's a lot of them. Fun backgrounds, too. But one kinda distracting thing is that the expressions seem very off in places. Characters are often crying when a more subdued emotion would work better, and some faces look just plain unfitting for the dialogue. And nobody's getting (physically) hurt here, so what's with the bandages? It's quite a nitpicky complaint, but I think facial expressions are really important for more subtle characterization and development in a VN-- a picture tells a thousand words, and all.
I was only able to get Ichirin's good ending on my first go, but then I went back and got Aya's and Wriggle's good endings as well, as the correct choices seemed obvious in retrospect. I still don't know which choice branches in the Prismrivers' story get you the good ending, let alone what the right options are... and I think that's kinda cool. In general, I really like how the choices are made, as well as what effects each choice has.
Though, I have a question about Wriggle's route. ROT13: Cnegjnl guebhtu Jevttyr'f ebgr, Pveab nfxf "V qvqa'g qb abguva' jebat, qvq V?" be fbzrguvat gb gung rssrpg. Naq, ba zl vavgvny cynlguebhtu, V jvfurq gb cvpx "Sbetvirarff" ohg qvqa'g, fvzcyl orpnhfr "V sbetvir lbh" naq "lbh qvq abguvat jebat" ner irel qvssrerag fragvzragf. V flzcnguvmrq jvgu Pveab'f zbgvingvba, rira vs ure rkrphgvba jnf xvaqn ohttrerq-- ohg gung xvaq bs ahnapr vfa'g ernyyl cerfrag jura nfxrq "V qvqa'g qb abguva'jebat, qvq V?", naq V gubhtug vs V rssrpgviryl fnvq "lrf" gb gung, fur'q frr vg nf na rkphfr gb qb vg nyy gur rknpg fnzr oyhag jnl bire naq bire ntnva. Vs fur unq nfxrq fbzrguvat gb gur rssrpg bs "Qb ln ng yrnfg trg jurer V'z pbzva' sebz?" be "Jung V qvq jnfa'g GUNG onq, evtug?" V cebonoyl jbhyq'ir cvpxrq "sbetvirarff". Jnf guvf fyvtug qvfpercnapl vagragvbany?
Aya's route in general seemed pretty rushed. Sure, the stuff that Aya talks about is really interesting, but it felt super fast. It just seems weird that a famous journalist who has stoically kept their inner workings hidden for presumably hundreds of years would be so incredibly honest and open and introspective and articulate about their identity crisis with a mute girl they met five minutes ago. It was a little jarring, and almost makes me wonder if Kokoro has some sort of hidden ability to make people around her more directly express their emotions-- I'm pretty unfamiliar with her, so that just may actually be the case. The the ending also felt a little outta nowhere. I dunno if that's intentional, considering being really fast is Aya's whole deal, but it was really distracting. That said, I don't know how to make it all feel more natural, considering this entire VN happens in a single day.
That same overly-open-ness shows up in the Wriggle chapter as well, and serves to make that section feel... kinda dragged out? Not necessarily by the events, but in the way the characters talk about them. It feels like most of the scenes involve one or more characters directly explaining why they did what they did in the previous scenes. With so many characters interacting and bouncing off each other and going through drama, I think a slightly more show-don't-tell approach would help here. Especially considering the childish vibe of these characters, they really don't need to be so good at articulating their feelings. Let the characters' actions (and facial expressions) speak for themselves a little more.
Sorry there's so much criticism here, or if my tone comes across as annoying or snooty. This is an awesome game, and I'm still giving it a 4 or 5 stars in every non-gameplay category.
In short, 'twas emotionally adventurous.