Spiritfuck Shoujo Side Story Toilet Ghost Hanako vs Muscular Exorcist

Could use an English language version

Its sad when you know the story of Hanako
If you don't I tells ya
There is a group of kids who play in the school and the game they play is hide and seek
So Hanako hide in the toliet and while they're playing the alarm echoes though the whole city... Yes it was in 1945 when American B29 superfortress drop a nucler bomb on Japan. Hanako tries to breakout of the toliet but it locked then the mushroom cloud appears in the sky. The rescuers came to find her but there's no sign of living thing in there