Mystery manga containing supernatural beings
Manga
Mystery manga that contain supernatural/mythological/folklore beings. May only make mention of these things or may actually be set in a world where they're real. "Beings" includes creatures, spirits, youkai, gods e.t.c. People with supernatural powers are not included.
Only series focusing on or centred around said beings have been added. Only the first entry has been added if it's part of a series and manga only.
Only series focusing on or centred around said beings have been added. Only the first entry has been added if it's part of a series and manga only.

Manga, 10 vol, 2020
Me:-
Author:7
Contains youkai. Adapted from a novel.

Manga, 17 vol, 2015
Me:-
Author:7
Has a bit of everything (e.g. angels and tengu).

Manga, 4 vol, 2013
Me:-
Author:8
Contains mouryou. Part of a series, each adapted from novels.

Manga, ? vol, 2016
Me:-
Author:3
Contains supernatural beings such as vampires and demons. Adapted from a novel.

Manga, 12 vol, 1997
Me:-
Author:8
As the name suggests, contains ghosts. Has a sequel. Adapted from light novels.

Manga, 7 vol, 1999
Me:-
Author:3
Contains many Norse Gods/Goddesses in human form. Part of a series.

Manga, 2 vol, 2007
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Author:6
As the name suggests, contains mononoke. Part of a series, each one direct adaptations of every arc in the anime.

Manga, 4 vol, 2007
Me:-
Author:5
Contains witches and other supernatural beings. Part of a series.

Manga, 10 vol, 1999
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Author:6
Contains things called mushi; it kind of fits the bill of supernatural creatures so I've included it. Has a sequel.

Manga, 10 vol, 2009
Me:-
Author:5
As the name suggests, contains demons. Loses some of the "mystery" aspect of it as the manga progresses though.

Manga, 14 vol, 2009
Me:-
Author:8
Contains ghosts and spirits. Adapted from a novel.

Manga, 19 vol, 2003
Me:-
Author:10
Contains spirits/youkai/supernatural beings. Has a sequel. You'll want to read Tsubasa Reservoir Chronicle at the same time to make sense of the plot.

Manga, 10 vol, 1995
Me:-
Author:5
Contains many "exotic" creatures. Has a sequel.

Manga, 22 vol, 2018
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Author:-
Contains supernatural beings such as vampires. Adapted from a light novel.

Manga, 3 vol, 1999
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Author:9
Contains supernatural beings, gods and seirei. Spin-off of Discommunication but you can read this without having read it (though it does provide some context).

Manga, ? vol, 2015
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Author:6
Contains spirits and supernatural beings/urban legends. Adapted from a novel.

Manga, 5 vol, 2010
Me:-
Author:5
Contains supernatural and demonic creatures. Adapted from light novels.

Manga, 3 vol, 2012
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Author:6
Contains spirits/supernatural beings and death gods.

Manga, 18 vol, 2004
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Author:7
Contains ghosts. Loses the "mystery" aspect quite quickly though.

Manga, ? vol, 2009
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Author:6
Contains monsters and other supernatural beings.

Manga, 6 vol, 2020
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Author:-
Contains folklore/urban legends. Adapted from novels.

Manga, ? vol, 2022
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Author:-
Contains youkai. Adapted from novels.