The Haunted Bookstore - Gateway to a Parallel Universe - Novel Volume 3 was written by Shinobumaru with illustrations by Munashichi.

When Kaori learns that the young wife who lives next door will soon give birth, it should be a joyous occasion. But the mother-to-be leaves Kaori wondering about her own past. How in the world did she come to enter the spirit realm, all those years ago? And whatever became of her human parents? Little does she realize that the answer is far closer than she thinks. The kasha Nyaa, Kaori’s lifelong best friend, knows more than she’s ever let on, and she’s about to finally yield the secret of Kaori’s birth mother.