Solid first release. First time I'm seeing an AVN focus on an idol group, so I'm very interested in seeing what the future holds in store for your story, what subjects you touch on, what you explore/comment on, etc...
The tempo of the game is likely slower than most AVNs, but I think it's fine to have games with different pacings. You deserve a lot of praise for the text effects you employ, I don't think I've ever seen an AVN use so many, so much, it gives the gave its own identity, which is nice.
I found one continuity error, which is that I didn't peek on Alice, yet MC still had a line about seeing her room full of bears and her doing stuff when finding the teddy in the garden. Other than that, my main pet-peev is that it gets tiring seeing "a few minutes later..." so many times. Consider employing other phrases: "a short drive later", "a short walk later", or simply use none and just imply the passage of time.
Best of lucks with development, looking forward to the next release!