Token
Tokens (寄香 yosuga; "clinging scent") are items mentioned in Fatal Frame V. They are items that have absorbed people's residual thoughts and emotions. Tokens are used in Shadow Reading to allow the seeker to see traces of the token's owner to locate something lost. The token may be an item the subject wore on their person, a piece of their writing, a photograph, a lock of hair, or an object connected to a missing item (e.g. a box for a lost ring).[1] Using a token belonging to a deceased person can be dangerous,[2] as following their traces could lead the investigator into the land of the dead.[3]
On Mount Kagiroi, people to be used in the ritual at nearby Mount Hikami would have a piece of their hair cut off to create a token to remember them by, which would be kept by someone close to them.
Misc. Info
The word yosuga in Japanese refers to a clue or a memento, though it is usually written with different kanji.