|“|| Stiles: "You can't tell Derek, okay? There's a lot more to this that you don't know about, and just because you got the Alpha Bite-makeover doesn't give you a license to go around destroying people."|
Erica: "Why not? That's all anybody ever used to do to me. I used to have the worst crush on you. Yeah-- you, Stiles. And you never once even noticed me. Exactly how you're not noticing me right now."
Erica and Stiles' relationship was quite one-sided for the majority of the time that they had known each other, as Erica had an enduring crush on Stiles without any knowledge of this on Stiles' part. Their first on-screen interaction occurred early in Season 2, when Erica, a shy loner with epilepsy, had a panic attack while climbing the rock wall in gym class while Stiles and the rest of their class watched. Erica, embarrassed by her reaction and the teasing from the other students that followed, attempted to climb it again after everyone had left, only to have a seizure halfway through that caused her to fall off, though Scott McCall, Stiles Stilinski, and Allison Argent were there to save her.
Shortly afterward, Derek Hale, a newly-ascended Alpha intent to create a new pack for himself, offered Erica the Bite, which she accepted, leading her to become a Beta Werewolf; this cured her of her epilepsy and gave her a sense of confidence in her appearance and general demeanor that she had never had in her life. For the first time, Stiles truly noticed her at school, and though Stiles believed that the Bite could be a good thing for her, he and Scott still worried about negative consequences of this transformation.
However, Erica did not allow her feelings for Stiles to get in the way of her loyalty to her pack, and when Scott and Stiles figured out that Derek planned to turn another fellow classmate, Vernon Boyd, Stiles rushed to his house in hopes of talking him out of it. There, he met Erica, who wasted no time disabling his car, knocking him out by striking his head with part of his car's system, and tossing him in a dumpster. This back-and-forth between the members of the Hale Pack and those who would become the basis for the McCall Pack continued throughout the season, with Erica and Stiles on opposing sides who were both trying to identify and defeat the Kanima killing dozens of their town's citizens while also surviving increasingly dangerous attacks from the Argent Hunters led by Gerard Argent.
Overwhelmed by these threats and believing that they were not properly warned prior to being turned into Werewolves, Erica and Boyd decided to flee Beacon Hills in favor of joining a pack in a less-intense location, much to Derek's displeasure. Unfortunately, before they could do so, they were captured by Gerard Argent and his then-brainwashed granddaughter Allison Argent and brought back to the Argent House to be interrogated. Stiles, too, was eventually captured by the Argents and brought to the basement, where he attempted to rescue Erica and Boyd but was unable to do so before being assaulted by Gerard. Just as they were released by a repentant Chris Argent, they were once again captured, this time by the Alpha Pack, who locked them up in the vault in Beacon Hills' First National Bank for three months.
Stiles was unaware that Erica had been killed by Kali while in the Alpha Pack's captivity until a ice bath ritual was performed on Isaac Lahey to trigger his repressed memories of finding her body in a closet at the bank. Her death was then confirmed when Derek and Scott (with an assist from Allison) attempted to rescue Erica and Boyd and found her body there, much to Stiles' dismay. Like the rest of the members of the Beacon Hills packs, Stiles mourned Erica's death.
Erica and Stiles are known as Sterica or Reyinski by fans
Throughout Teen Wolf
In Ice Pick,
In Master Plan,
In Chaos Rising,
- Had Erica's actress, Gage Golightly, hadn't left the show at the end of Season 2 to film a pilot for The CW Network (which was ultimately not picked up), Erica likely would have been a love interest in Season 3. Instead, Stiles' character developed interest in Derek's sister, Cora Hale, who, in a way, replaced her.
- Erica had feelings for Stiles that dated back to elementary school, much like Stiles' crush on Lydia Martin. Stiles had no idea of Erica's feelings for him until Season 2 of Teen Wolf, just as Lydia had no idea of Stiles' feelings for her until that point.