Pumpkin Witch Nana Volume 1

Young siblings Danny and Wendy lived an ordinary life in a ranch left by their parents. One day, following a mysterious white rabbit, they found themselves in a totally different world. A world filled with monsters, ghosts, and undead--as if Halloween comes true. With no way back, there was only one person they could rely upon, and that person was a witch. She called herself, Pumpkin Witch Nana. And as an exchange for her help, the witch had only one request... and that is to repay her debt?