Fell from the pleasure boat "Eternal Maid II" mid-cruise in the waters near Rokkenjima.
On October 4, 1986, she drifted to Rokkenjima, and the Ushiromiya family welcomed her as a guest.
She managed to drift to the island unharmed thanks to several miracles, including the fact that she was wearing a life jacket.
Bernkastel's double and servant. Also a piece who has manifested in the human world.
Because she is human, she cannot use magic and the like. However, she can appeal to Bernkastel on a higher-level plane to obtain miracles and various authorities she can use, so it would probably be no exaggeration to call her a human capable of wielding the power of a witch.
Through Bernkastel, she has been given the detective's authority while on the game board.
The Witch of Truth (provisional). Is also the detective and one who calls herself an intellectual rapist.
She participates in Battler's game as a player for the human side.
She possesses several skills that qualify her to call herself a detective. These can be acknowledged by Bernkastel and elevated to the level of red truth.
Whether she wins or loses, this will be the last game, and there will be no further use for her.
The Witch of Truth, who has successfully revived from the depths of oblivion. She is an enigma, a witch who is also a detective and a human.
Once again, she will serve her master Bernkastel in her scheming.
Background
Erika claims that, some time in the past, she fell in love with and began dating an unnamed man. Over the course of the relationship however, Erika began gathering evidence that her boyfriend was cheating on her with another woman. Despite only having circumstantial evidence, Erika confronted her boyfriend and he broke up with her. The ordeal sparked an inferiority complex and strong denial of love in Erika that persists throughout Umineko no Naku Koro ni.
In October 1986, Erika falls from the "Eternal Maid II" cruise ship in the storm that envelopes Rokkenjima. As a result, Erika is taken by the sea and washes up on the shore of Rokkenjima.
Appearance
Erika appears as a young girl with dark blue eyes and hair, made in Bernkastel's image. The elaborate dress she wears actually belongs to Jessica. Despite this, the dress is not imprinted with the One-Winged Eagle in any visible location. In addition to the pink and white dress, Erika also wears a flower accessory on her head.
When Erika marries Battler she wears a traditional white bridal gown and white gloves though the One-Winged Eagle is visible on the headdress and on the waist of the dress.
While serving as Commander of the Library Fleet, Erika wears a pirate hat. This hat did not appear in the original visual novel and is only visible in updated sprite sets. The logo on the hat changes between adaptations; in the Alchemist sprite set, the logo is a cat-like jolly roger, in the Pachinko sprite set, the logo is a skull, and in the manga the logo is a combination of a cat, a rose, and a scythe.
Personality
Erika is highly intelligent and possesses a photographic memory. While in public, she maintains a polite appearance and shows interest in little other than mysteries. In reality, however, Erika is ruthless and enjoys solving mysteries only for the pleasure of denigrating those who pose them to her. Her malicious personality is derived from an inferiority complex developed early in her life.
She is particularly attached to Dlanor A. Knox as she is one of the few people who is kind to her.
Plot
End of the Golden Witch
Erika first appears in End of the Golden Witch as a piece made by Bernkastel to serve as detective. She washes up on Rokkenjima after falling from a cruise ship in the typhoon surrounding the island. After the events of the first twilight, Erika declares herself as the detective and attempts to determine the culprit behind the murders. Using a litany of circumstantial evidence, she determines that Natsuhi Ushiromiya is responsible, despite Natsuhi's constant protests to the contrary. In the process, she successfully denies the existence of magic altogether, resulting in Beatrice's death.
In the Tea Party, Bernkastel gives Erika the temporary title of "Witch."
In the ????, BATTLER is given the powers of a witch by Lambdadelta and challenges Erika, claiming to have a plausible theory to the first twilight wherein Natsuhi is innocent. The two battle using the Red Truth and Blue Truth, however the battle ends in a draw. Much to Erika's despair, Bernkastel considers this to be a loss.
Dawn of the Golden Witch
Bernkastel uses Erika again in Dawn of the Golden Witch, though Erika finds that she is unable to use her previous tricks thanks to BATTLER's changes to the Game Board.
During a conversation with Dlanor A. Knox, Erika reveals the past behind her embittered personality; Erika had come to believe that a previous boyfriend was being unfaithful due to circumstantial evidence. Regardless of his protests, she could not be persuaded otherwise, leading to their break-up. Dlanor attempts to tell Erika that, since humans lack the ability to use something like the Red Truth, she is only hurting herself by attempting to solve human issues with her cold logic. However, Erika refuses to acknowledge this.
After the first twilight, Erika attempts to claim victory for the Human Side without the use of detective's authority. She does this in order to conceal her true plan of forcing BATTLER into making a Logic Error. With the help of Bernkastel and Lambdadelta, Erika tricks BATTLER into allowing her to use three rooms worth of tape seals. Using this, she successfully tricks BATTLER into creating a Logic Error, trapping his soul inside. As a reward for her victory, Bernkastel organizes a wedding ceremony between Erika and BATTLER's soulless body so that Erika can take his successor ring and become territory lord of Beatrice's Game Boards, allowing her to humiliate BATTLER for the rest of time. During the wedding reception, a reformed Beatrice crashes the wedding and challenges Erika to a duel.
After losing to Beatrice and BATTLER, Erika is banished to the depths of oblivion, her location known only to Bernkastel.
Twilight of the Golden Witch
During the Halloween after-party, Dlanor A. Knox tells BATTLER of her inability to deliver Erika's invitation due her banishment in Dawn of the Golden Witch. After BATTLER and Beatrice solve the final game, Erika is released from the depths of oblivion. She arrives at the Halloween after-party in time to save Ange Ushiromiya from a group of Goats.
Some time later, a massive number of Goats begin swarming the island and Erika returns, under Bernkastel's command, to fight BATTLER one last time. After ANGE-Beatrice defeats Beatrice in the chapel, Erika leaves the fight with BATTLER. She is later made the Commander of a fleet of ships ridden by countless powerful Goats and is instructed to destroy the Golden Land. She is briefly stalled by Beatrice, however she eventually succeeds in destroying the Golden Land, defeating Beatrice, and taking her still-beating heart.
Erika appears in the "Trick" ending after Ange murders Juuza Amakusa and Captain Kawabata, congratulating her for finding her own truth.
In the Tea Party, she visits Bernkastel and Lambdadelta and receives a letter from Dlanor A. Knox regarding the well-being of everyone in the Great Court of Heaven. The letter includes a request for Erika to stir up trouble so that Dlanor has something to do besides paperwork.
If paired with Bernkastel, the two begin their assault on the Golden Land per Twilight of the Golden Witch. They fight against George and Rosa Ushiromiya and later fight against Beatrice and Battler Ushiromiya for their final stage.
If paired with Dlanor A. Knox, Erika concludes that Natsuhi Ushiromiya is the culprit per End of the Golden Witch and attempts to prove that no other explanation is possible. They fight against Beatrice and Battler Ushiromiya and later fight against Shannon and Jessica Ushiromiya for their final stage, during which Jessica uses her alternate sprite set.
Erika was originally supposed to appear in Land of the Golden Witch as a man named Virgilius. Once Land of the Golden Witch was scrapped, the name was given to Virgilia and his personality was given to Erika. This is further revealed in Last note of the Golden Witch.