Her father was J. Reyes, the insurance adjuster who investigated the car crash that killed Jackson Whittemore's parents in 1995.
She suffered from epilepsy and the medication she took caused weight gain and acne. As a result, she was a “pariah” at the school and thought of herself as unattractive. Derek Hale seduced her with the promise that the bite to make her healthy and beautiful. The transformation gave her more confidence in her appearance and social life.
However, she was caught in the middle of a conflict with Hunters and a Kanima and attempts to flee with Boyd but is captured by the Hunters. Despite escaping, she and Boyd are captured again this time by The Alpha Pack.
While being held captive, Erica talked with Boyd about what will happen to them during a lunar eclipse. She wonders if it will make them stronger and then says that she hopes it will. She then gets up and attacks Kali only to be killed by the Alpha. Her body was stashed in a closet and later discovered by Allison Argent.
Erica trained with Derek and Isaac and, in a move to be unpredictable as instructed, wrapped her legs around Derek and began kissing him. He says she can't do that again because he has someone else in mind for her. (Read More...)
Erica is sent by Derek to get Jackson and later to test and kill Lydia Martin. She manages to flirt with Scott (with her hand on his thigh) and threaten Allison (with extended claws on her thigh). Later, she manages to catch an arrow from Allison's crossbow but is incapacitated because Allison had treated it first with the Kanima's paralytic venom. (Read More...)
Derek sends her to question Stiles to make sure Jackson is the Kanima. She gains Stiles' trust and offers an exchange of information. She tells the gang about Jackson's real parents and how they died in exchange for confirmation that he is the Kanima. She admits that she used to have a crush on Stiles. She is later injured by Jackson. Derek breaks her arm to start the healing process. (Read More...)
As part of the plan to capture the Kanima, Erica and Isaac distract and drug Jackson at the rave. (Read More...)
On the night of her first full moon, Derek tries to lock Erica, Isaac and Boyd inside the old subway car in the lair. She transforms and manages to escape her bonds. She attacks Derek but is subdued and secured once again. (Read More...)
Erica and Boyd hear what they believe is the howling of another pack of werewolves. They decide to leave Derek and take their chances alone until they find this new pack. Unfortunately for them, the howling was a recording. A trap set by the hunters. (Read More...)
The Argents truss Erica and Boyd up to a ceiling beam in their basement with electrical wire. The electricity coming through the wires is enough to keep them from transforming. Chris Argent has a change of heart and lets them go. She and Boyd are running through the woods until they encounter a group of individuals with claws and hear a howl. (Read More...)
Erica has been missing for four months. She is seen briefly on a missing persons poster in the hallway of the school. Derek says The Alpha Pack has both Boyd and Erica in an undisclosed location. A hand, only glimpsed for a moment in what appeared to be a bank vault, is believed to be Erica. (Read More...)
The hand holding Boyd's turns out not to be Erica's after what appears to be her corpse was seen in a store room in an abandoned bank building. Earlier Isaac said under hypnosis that he knew she was dead before his memory was taken from him. (Read More...)
In Boyd's flashback, Erica fate is revealed which leaves Derek in shock and grief. (Read More...)