|Allegiance:|| The Clave|
|Significant other/s:||Helen Blackthorn|
|Parents:|| Patrick Penhallow|
|Eye color:||Dark Brown|
Aline Penhallow, Sebastian Verlac's striking cousin, is said to be Isabelle's opposite. She is conservative on the subject of Downworlders as well as being curious about many subjects, especially vampires. Aline has a short-lived crush on Jace, to which she makes a move. However, nothing comes of it, and it is revealed that she is a lesbian and currently dating Helen Blackthorn.
The Lightwoods and the Penhallows have known each other for years. Once, when the Lightwoods were visiting, Jace wanted to explore Brocelind Forest. When they got there, they got lost. Aline was terrified that they would die there. However, Jace confidently, after hours of attempts, managed to lead them out of the forest.
City of GlassEdit
Aline is at her house in Idris, waiting for her longtime friends, the Lightwoods, to arrive. At the same time, her cousin, Sebastian Verlac, was visiting from Paris as well. When the Lightwoods arrive, carrying an unconscious vampire with them, Aline is curious. She converses easily with the Lightwoods and questions Simon about his species.
Aline has a short term crush on Jace. During that time, she kisses him, only to be inturrupted by Clary, immediately putting her in Clary's bad books. However, when the teenagers of her residence were discussing Jace and Clary, Aline comes to Clary's defense. She points out that Jace should lighten up on his overprotectiveness, though she misunderstands why Jace is protective, as she believes they are siblings.
Everything changes one night. Suddenly, the Demon Towers of Alicante seem to go out, and demons swarm into the city. Several break into Aline's house, driving her out into the streets. While outside, Aline is knocked to the floor by a demon who then attempts to rape her. However, Aline is saved by Isabelle Lightwood. Then, she kills the demon from behind before running off.
When Aline is next seen, her mother is being yelled at by Maryse Lightwood. Her cousin, Sebastian, had just killed the youngest of the Lightwoods, Max Lightwood. Aline was in contact with Elodie Verlac, Sebastian's aunt, who sent some of Sebastian's things as well as some pictures. This reveals that the person that was staying with them was an imposter. Instead of telling her parents or the Clave, Aline goes to tell Clary Fray. She hoped that Clary would tell the Lightwoods and that they might forgive her family.
Aline is with Isabelle and Clary as they discuss what they'll be wearing to the party. After she leaves, Isabelle asks whether or not Aline was jealous. To this, Clary replies no, signifying that they were on good terms. She is last seen at the party in Alicante.
City of Lost SoulsEdit
Aline is seen at the Council meeting to discuss what should be done about Jonathan Morgenstern. She is afterward seen with her girlfirend, Helen Blackthorn, talking to the Lightwoods and Clary.
She participates in the battle against Jonathan Morgenstern alongside her girlfriend Helen, the Lightwoods, Simon Lewis, the New York Pack, and Magnus Bane. She covers for the group not telling the Clave about the attack by lying to her mother. She said that there wasn't time and that they needed to go when they received the information. She does this as an act of revenge against Jonathan, who killed her cousin Sebastian, as well as a thank you to Isabelle, because she stopped a demon from attacking her.
Aline is described as "striking" by Simon Lewis. She is half Asian, lending to her curved cheekbones and eyes. She also had black hair that she recently cut to just above the shoulder. Her dark brown eyes are a sign of her Asian heritage and she is said to look a great deal like her mother. She is described as not exactly pretty, but striking nonetheless.
Aline is in many ways Isabelle's opposite. Where Isabelle is outspoken and confident, Aline is conservative and somewhat shy. She is very caring toward her friends, the Lightwoods, and tries to console them when Jace was kidnapped. She is hesitant about the topic of downworlders, being raised in Idris, and asks quite a few questions about them to Simon when they meet. She initially believes that downworlders don't have souls, and bluntly says so to Simon. The two are a great deal alike. They both say whatever comes into their head's when it comes into their heads.
Despite her hesitant nature, Aline does care deeply for her family as well as the Lightwoods. She doesn't tell the Clave about the actual events occurring during the fight against Jonathan as a form of revenge against him for killing her cousin. This is also payment toward Isabelle, who saved her.