Lovely read. I liked it overall though maybe there are two things that didn't stick with me:
*the pacing of the story constantly slows down for the intellectual talk the characters always drift into. So in my eye it looked like "Here we go for 2 minutes-> cultured talk for 7 minutes -> repeat". Not that I don't appreciate the topics, I guess it does happen IRL too, but the pacing alternating between the frank short waves and the philosophically dense and slow waves puts me off balance. Or maybe it's not about the pacing but how there are so many different topics in a row, instead of exploring one side of a central theme.
*also, I think Reimu doesn't do much herself. While Reimu admires Marisa's tact and cooking and personality, Marisa just doesn't visibly return the favour as much. Maybe it's because Reimu's the main protag here so we know only her thoughts, but I'd have liked Marisa to say or show something to Reimu too, or have Reimu have her cool moments too so that Marisa can compliment Reimu - in short I felt the affection looks rather one-sided
Despite these, the entire story manages to be a good buildup to the ending so it's all cool.
I featured this game in my showcase video even though I can't really do much aside from small comments here and there:
https://youtu.be/QJnqeaYY4Xk?t=237