the full game can be purchased on itch.io?
Viewing post in Syahata's bad day(v1.0.5) comments
Itch.io had problems with the game, so you can't purchase it here, but you can purchase it on Ci-en, Fantia or on DL site
https://www.dlsite.com/maniax/circle/profile/=/maker_id/RG01006052.html.