Selina looks exactly like the young version of her great-grandmother.
Not much is known about her early life. She was born to one of Eva's descendants at an unknown time. At some point she met Mathias and together they opened a Santeria store in New York.
Before Eva died she had left Killian an unbreakable statue with an address on it to help him reunite with Freya. The address on the statue was actually the location of the Santeria store. After Mathias tested Killian, Selina gave him a poison which would kill him but also break the star-crossed fate he has with Freya so that in their next lives they can be together. She also told him that there is no antidote and that she has never met anyone who loved her as much as he loves Freya.
Mathias - Friends and coworkers
Killian - Acquaintances/allies
Powers and Abilities
Selina is a witch who practices Santeria and possesses the basic powers of a witch. It is unknown if she is immortal or not as Eva and Alma were mortal.