Responses
It is based off an old Cantonese song with the same title by Fiona Sit which carries similar themes of unrequited devotion and faith where a fan writes letter to Keanu Reeves for years without fail, expecting nothing back only to recieve a handwritten reply in admiration for their persistence and love. If you read books, you should really give the original novel a go :3

What does Keanu Reeves gotta do with this