Selena Harman is a witch and a member of the Harman family. According to the family tree, she is the eldest daughter of Edgith Harman, the older sister of Sophia and Nissa and the adopted mother of Aradia Crowley. This would also make her the maternal aunt of Thea and Blaise. Selena neither appears nor is mentioned in the books, only on the family tree.
- Selena is the Latin form of Selene, which means "moon" in Greek and is the name of the Greek Titan moon goddess. This would make Selena's name a traditional witch name.
- Selena's name is very similar to that of another witch character, the Circle Midnight witch Selene Lucna.
- There is some debate as to whether Selena being Aradia's adopted mother is actually canon in the novels. Aradia is never mentioned in the books as being adopted into the Harman family; it also seems strange that Aradia has the surname of Crowley and not her adopted mother's surname of Harman. The family tree is also known to have several discrepancies and errors.