Erin is the daughter of Robert & Penelope (Penny) Ambrose, and an only child. What begins as a regular day quickly turns to tragedy when Erin returns home to find her parents murdered. She quickly comes under attack from Morgan Slade, 'Sparky' & 'Gauss', who were the killers. Luckily she is saved by the arrival of two strangers - Jake Stryker & Chris Angelus. With nothing left, Erin leaves to go with Jake & Chris to discover more about her heritage, and hone her skills so she can avenge her parents death.

At the time of the attack, Erin is still unaware of her abilities and only discovers them after Jake persuades her that she must have one.

SPOILERS

During the ongoing conflict, Erin's need to avenge her parents death leads to her capture by 'Sparky', after which she is imprisoned in Slade's island fortress in the pacific. During this time, Slade takes a sample of her DNA for his research, and she is constantly taunted by Loki. She manages a brief escape to warn Jake & Chris, but is soon recaptured. She later seduces Loki and turns him to ice.

Erin is later taken to witness her friends demise, and Slade's superiority. Chris ends up captured, and Jake ends up slashed and defeated. Erin witnesses her friend's death, which leaves her even more distraught since he was her knight in shining armour.

After those events she got to know Bryce Varner, after they both moved in to Jake's manor. They eventually started dating, and were a couple during Damien Slade's attempts at world domination. During this time she fell pregnant and had a son, ???.

Shortly after giving birth he was kidnapped, leaving her grieving and vengeful. She eventually gets her son back, and kills his captors. After these events, she settles back down to take a parenting first approach much like Jake once did.