Erika Furudo (古戸 ヱリカ Furudo Erika?)
Voiced by: Natsuko Kuwatani
Erika is a young detective introduced in End of the Golden Witch.
A blue-haired girl estimated to be around the age of a middle school student, she is characterized as being highly intelligent and possessing an excellent memory.
She acts very polite in public, and shows an extreme interest in puzzles and mysteries.
In truth, she is ruthless and cunning, and only solves mysteries to boast her superiority towards those who execute them.
She does, however, possess a serious inferiority complex, and is prone to breaking down emotionally whenever things do not go her way.
Erika had been presumed lost at sea after falling off of a boat near Rokkenjima around the time of the murders.
By the time public interest about Erika's fate arose,
she was written into the stories of End and Dawn of the Golden Witch as having washed up on the shores of Rokkenjima
being taken in by the Ushiromiya family as a guest.
From a magical perspective, Erika was a piece added to the game board by Bernkastel, created in her (and Lambda's) own likeness, to serve as the game's detective and investigate the murders presented in the core arcs, interacting with characters from the meta-world to formulate her theories.