"Happy happy happy ♪ ♬ ~..All is so gloomy ~"

"Huh? what's that? "

I look up from my book to look around the empty park. Such a weird song, who's singing it, I wonder. It's been some days that I've been coming to this park at end of the neighborhood. A quiet and empty park, some swings and seesaws, nothing more. I haven't seen many people coming here at all, just some elementary students making a racket sometimes, but they too don't come here much, might be because it's surrounded by huge trees and it's also quiet...