Yes, it's a confusing movie but I like the plot :D I've watched it for nth times to translate and understand the meaning. Like Nemo-Anna relationship here :)

No, it's kinda mystery-thriller movie, not horror (I hate horror movie). It's a detective story about murder cases based from urban legends at their town.

Hmmm, I've never send letters XD I don't know about the mechanism but maybe I wanna try :D