 | Name | Hydrological Studies in Byakuyakoku |
| Type (Ingame) | Quest Item | |
| Family | Book, The Byakuyakoku Collection | |
| Rarity |  | |
| Description | This text records the geography and hydrology of Byakuyakoku. With the sealing of the depths and the emigration of the people of Watatsumi, as well as the passing of long years, this book is now useless. |
it's a skin