Since Leesihan's earliest memory, she had been alone. After getting kicked out of her home at the age of five, she survived the Backstreets of District 9 for the next ten years on her own. When she was 15, a man gave her shelter for one night out of the goodness of his heart, and one night became many. That man became her first boyfriend, but this..."relationship" wasn't meant to be. She learned it was a terrible idea to date a partner almost twice her age, killed the man, and recruited another girl he was victimizing to start her own Syndicate called the Dissonant Keys, named after her love for piano. Her lofty goal was to become a rival to the Five Fingers; although she knew that was nigh impossible to achieve, she acted like it wasn't.

Rather than go down a path of meaningless crime preying on the weak, Leesihan desired her Syndicate to be one that would go after others. During the early days of the Dissonant Keys, she ran into conflict with a rival Syndicate. Her second boyfriend at the time had fled from the Syndicate due to a debt he owed to their leader, and if Leesihan refused to hand him over, they would wage war against her gang. Her spy network predicted the Dissonant Keys would win, but not without immense losses. Fighting this war could destabilize her entire Syndicate and lead to its collapse. Between letting go of her dreams or her partner, she chose to take her boyfriend out on one last date to his favorite restaurant, where they ate a wonderful meal. Afterward, she lead him into a secluded alleyway where she knocked him out cold. She passed his unconscious body over to the rival Syndicate's leader, and they agreed to truce.

Leesihan continued to build up her gang. She was more than capable of hand-to-hand combat, but the key to her success was reconnaissance. As she recruited more people into the Dissonant Keys, she created an elite squadron of spies that infiltrated other Syndicates to gather information and sabotage their plans. Her determination allowed the Keys to become a more successful Syndicate than most, with their territory spanning half of the District's Backstreets and forces numbering in the thousands. Within a matter of weeks, she would get her revenge on the Syndicate that killed her beloved and decorate the streets with their leader's intestines.

Several years later, her dream came to an end when the Ring conducted a raid on her headquarters. Her girlfriend, her third partner and a member of her inner circle, turned out to be a double agent for the Ring and provided them with crucial information about her Syndicate. While the Ring wiped out Leesihan's forces, she was forced to kill her girlfriend-turned-traitor in battle, after which she fled to a safehouse on the other side of the district. She cursed the Ring and her spy-turned-traitor, but she couldn't bring herself to be mad about the way her Syndicate ended. It had to be karma for the way she betrayed her previous boyfriend.

One week later, she was frightened by a letter penned to her address. But its sender wasn't the Ring, nor any Syndicate. It was from a Wing—Lobotomy Corporation was offering her an opportunity to work at their main branch, even though she never applied. To her, feathers were chumps who sucked up to their superiors all day and treasured their boring jobs like religious worship. But between staying trapped in her safehouse for fear of the Ring or joining a Wing, she knew what she needed to do in order to save her life.

Leesihan's skills lend well to her role as Information Team Captain. She is organized and meticulous in her methods of storing data. Her handwriting is neat and easy to read, albeit large, and her writing style is unneccesarily flowery. Being an early riser, she is always first to arrive at work and first in line at the cafeteria. She takes pride in her efficacy; the quality of her work is so high that even Yesod can't find a fault in it.

Speaking of Yesod, employees will notice that Leesihan is subtly terrified of being in his presence. She claims she simply does not like him, but she has yet to tell anyone that she can't stand him because he has the same voice as her dead boyfriend.

Contrary to her work ethic, her personality is...distateful, to say the least. Feathers may mistake her as one of them due to the way she carries herself until they actually meet her, to which they swiftly realize she very much comes from the Backstreets. Her language is crude—she flings cuss words in her everyday language, and frankly doesn't give a shit if her remarks offend you. She is as brash as she is bossy and tries to keep conversations short because she does not enjoy entertaining others, but when she needs to be, she can act surprisingly charismatic. For someone so observant, she's quick to make assumptions about people and stubbornly sticks to them, often until it is too late to make amends.

That being said, some who grew up in the Nests find her rude behavior particularly refreshing. It's easy to tell that she is very blatantly being herself, throwing social etiquette and manners out the window. She knows the manager won't get rid of her because she's simply too valuable of an agent. Also, if there's one thing that everyone can agree on about her, it's that she's damn hot, something she's capitalized on a lot.

She does not immediately take action during Abnormality suppressions. Rather, she prefers to assess the situation first before deciding on the best course of action for her and her subordinates. Unfortunately, that requires her to relay her plans to Mason, the asshole in charge of the Control Team. Sometimes, he has the audacity to suggest that she's wrong, and it would almost lead them to bicker back and forth if it weren't for the pressing situation or the manager's orders overriding either of their authorities. That isn't to say she won't enter the battlefield unless there's a plan, but she's of the belief that it's always good to have one.

Having been betrayed by each of her partners in different ways, she keeps people at an arms length. A method of protecting herself, but not in the way one might think. Sure, it means that if she's betrayed again it won't hurt her as much, and she won't be caught up in grief if they happen to die. But as a leader, it is her responsibility to ensure the collective safety of those following her, and if that requires sacrificing someone close to her, she would like to mitigate the remorse she will feel from betraying someone's trust again.

Leesihan preferred to work alone during her first few days at Lobotomy Corp and even after her promotion to team captain. However, that began to change when a co-worker named Taengtaeng was assigned to her department. Taengtaeng's willingness to obey orders reminded Leesihan of her most loyal spies in the Dissonant Keys, the ones who fought to the bitter end to ensure her safety during the Ring's raid. At first, she believed Taengtaeng's loyalty was simply an extension of her eagerness to from landing a job at a Wing, but Taengtaeng herself quickly confessed it was Leesihan's adamant personality that she admired and wished to follow her because of it. That kind of earnestness was rare in the Backstreets, and out of respect, Leesihan became more willing to open up to her.

They befriend each other in every loop. Most of the time, their relationship quickly shifts into something not very platonic, allowing Leesihan to lower the wall she has put between her and other people for so long. She vows to protect Taengtaeng no matter what the cost, even if it means letting the entire facility die just so the two of them can stay safe. She is aware of how selfish her priorities have become, but she will not allow herself to make the same mistake twice.