Mysterious man in Gensokyo

The story of a man named Kenshi Takeda, a university student, who cannot remember his own past. The only thing he can recall is a girl from his recurring dreams that have haunted him for years. However, fate leads him to Gensokyo, where he discovers connections to his forgotten past. Now, he must strive to uncover the forgotten past and survive the dangers that come in his way.

Note: I don't own the characters, plot, locations, or any historical context beyond my own original story concept and fan fiction.