Harriet Violet, before marrying Adamska Violet, had brief relations with Aaron Goldie, becoming pregnant from the encounter. Aaron, frequently having such trysts, barely remembered the encounter afterwards. Harriet married Adamska before giving birth to the twins Eva Violet and Juliet Violet, so he was legally recognized as their father. This secret was kept for many years until Juliet was set to be betrothed to her half-brother Morris Goldie to bind the families together, and Harriet's attempt to stop it without revealing her secret was the cause of all events of the tragedy on the island.
Due to Ritsuka Fujimaru's consciousness being sent into that of Juliet's friend, Ritsuka is unable to comprehend all of the sensory data in regards to humans through that connection. Ritsuka views them as Servants contracted to them, Harriet appearing as Euryale. The assigned Servants may have some connection in terms of personality, but it is possible for key traits of the person to be confused due to the process. In the case of Harrit, she has a similar appearance to her daughter Violet, who is portrayed as Euryale's sister Stheno. Her other daughter Eva takes the appearance of the motherly Raiko. This causes a fundamental misunderstanding for Ritsuka for the majority of the incident.