After death, Sania is reborn into a quiet world called Limbo. She is born a princess alongside her sister Amara, into a nation ruled by balance, faith, and love-but Sania remembers none of her past life. No tragedy. No god. No reason she feels so deeply connected to dreams she doesn't understand. As she grows, the world reveals its rules slowly: magic granted by belief, a church that claims divine knowledge, and a fragile peace between nations that fear what they don't understand. When a sacred ceremony goes wrong and cracks form in the sky, Sania becomes something the world was never prepared for. Caught between the church that wants to claim her, the nations that want her erased, and a fate shaped by faith she cannot remember choosing, Sania must learn what sanity truly means in a world where even gods can break. A quiet fantasy isekai about memory, belief, and enduring love-The Book of Sanity is a companion story to The Book of Madness, told from the other side of death.

What if hidan and sakura did meet at young ages and will they still be friends as they grow up and is their certain stuff that is going to hold them both back? Well you will have to find out!

An illegitimate 12 years old torn between 2 families, ruined by her step brothers and saved by her new found step brothers, she yearns for love acceptance and warmth