Has anyone researched Naoki Hisaya ? His works after Kanon seems to be too close with Kanon, with a shared general plot.
“Sola” which is a manga he made for example. The girl can possibly be compared to Ayu, and the progression of the main protagonist can be compared to Yuichi at certain points. In Kanon, Ayu (Ayu route spoilers) disappears around the mid-part of her route, just vanishing without a trace and in Sola, (Matsuri Spoilers) Matsuri disappears, after the main protagonist tries getting her the tomato juice, and is seen later in the church If we compare the 2 girls with routes with the spoilers that we have of them, we know that (Kanon - Ayu & Sola - Matsuri spoilers) Ayu and Matsuri are not ordinary humans. While Ayu is a human, she’s technically a soul without a body present, and with Matsuri, she is not a human, but a creature from the night who can live forever but does have flaws in that lifestyle.
They also have the same obsessions for stuff. Ayu craves Taiyaki, and Matsuri craves Tomato Juice.
The other work that he did was “Celestial Method” and, though I haven’t seen it, the plot is too familiar with Kanon. This is what the plot says, so I’m guessing I don’t need to spoiler tag this
“Nonoka Komiya is a girl who once lived in Lake Kiriya City, based on Lake Tōya in Hokkaido, where she met a blue-haired girl named Noel. Seven years later, Nonoka returns to the city, which now has a mysterious saucer floating above it, and reunites with Noel, who promises to grant her wish.” ~ Wikipedia
Though it is different, you can kinda tell it’s a copy at the same time.
I know as a writer, you tend to have the same concepts, but Naoki should put some effort into making a greater story. Naoki has the possibility of making a greater story than Kanon if he tried hard enough.