Hi! I enjoyed the game, but I noticed something that may be wrong about the use of Hiragana/ Katakana in the character art.
I could be wrong, as I don't have too much fluency surrounding the language, but I'm part Japanese, so I have some familiarity with the usage of Hiragana and katakana for names.
In the names for Axel, Aiden, Cain, and Isaiah, it's all written in Hiragana. Hiragana is the simplest writing style for the Japanese language, but it isn't used for foreign names like Cain. When a word or name is foreign, Katakana is used because Hiragana is meant for Japanese words or concepts. Katakana helps distinguish things as being foreign to the language. The only Name that would be written in Hiragana/ Kanji is Haruto's name because it's Japanese, which was actually the only name written in Katakana.
Its relatively minor as they aren't really seen in the game, and don't take up much of the promotional art of the Male leads, but I thought it was important to bring up. I can't help much with finding out how to write those names correctly, but I hope this is helpful in some way, if I'm not wrong about my criticism.
Otherwise, keep creating! I'm curious about the game's story (and Axel, I love nerds)