Right after graduating from high school you move to Guan Island, a technology center created on an artificial island south of Japan, where you plan to follow in the footsteps of your deceased mentor, carrying on her research in artificial intelligence. But until that day comes, you will live with her daughter, who is also your childhood friend (and also the girl you love).

However, thanks to a red-haired girl appearing in your dreams every night you embark on a journey to learn about lucid dreaming.

[From Itch.io]