Eileen is not petite, but is certainly unassuming, and easily overlooked. She does not have heroic proportions by any means, and is a bit on the short side with a small frame. She usually wears her dark, shoulder-blade-length hair in a small ponytail, and wears glasses for purely cosmetic reasons.

Eileen dresses vary casually, usually sufficing with a T-shirt and a skirt, since she will almost always have a white lab coat draped over the ensemble. She is so casual in fact, that she even often wears flip-flops and sandals in the lab (Gasp! A safety violation!) but since she is usually master of her own lab, there is no one to punish her.

Eileen is soft-spoken and big-sisterly, often displaying cute, ditzy mannerisms. She can get excited when talking about technology or research, but is quite subdued most of the time. Yet her slow, quiet speech is accompanied with a certain gravity. She is very nurturing to her teammates, motherly as she takes care of their needs while also pushing them to challenge themselves and improve. Her quietness, at times, seems forlorn and determined as she stares off into some brave new future that she knows will one day come.

On the other hand, her personality slightly changes when she dons her power armor. Half of her powers being based off sound, Eileen understands the value of being loud, and often utilizes shock and awe tactics. In combat, she can be exacting, precise, and relentless. Control defines her, whether that is mastery over herself or the battlefield. She is determined to push onward and use the most optimum method to get the job done.

Eileen was born to a poor immigrant Chinese family in Oakland, California. Living in a low-income household, Eileen was taught to obey the established peace and order, to not cause trouble, and to strive for self-improvement.

At a young age, Eileen demonstrated a knack for complex mathematics and, by extension, physics. Through study and hard work, Eileen saw that she could live a perfectly peaceful and successful life. Complacently and blindly, Eileen powered through her education, gaining multiple honors and advanced degrees. Though praised as a prodigy, Eileen remained humble and reserved. She eventually found herself moving to NAC and working in government laboratories, developing cutting-edge technology for the various failed projects of DIM, with whom she agreed with philosophically. Hosts were too dangerous, and order must be maintained. What she disagreed with, however, was DIM's methods. But what could she do? She was just a researcher.

One day, she woke up, her head filled with white noise, and her vision blurry, her skin sensitive. Her senses were competing for computing space in her brain. She tried to hide from all light sources, she tried to muffle all sound, but it helped minimally. Realizing that she might be going through an Imperium infection, she called her work and explained the symptoms. They came and collected her, dumping her, as requested, into a sensory deprivation chamber, that she had requested also be RF insulated. In the silent darkness, she was finally able to gather her thoughts. Her Imperium had made her skin able to sense two wave phenomena: light and sound, visible and invisible, audible and inaudible. With the help of her workplace, she slowly trained her brain to filter what she was normally supposed to be able to see and hear as a human, from the bombardment of white noise and RF static that a human was not supposed to be able to see or hear. Then she trained herself to tune in to that noise and static, to learn how to identify and interpret. She made herself a willing guinea pig to DIM, so long as they respected her rights within reason. But more than anything, her newly gained ability to detect both sonic and photonic harmonics accelerated her research into crystalline optronics, pushing the boundaries of robotics.

Now, as one of the few hosts working within DIM, Eileen plans to revitalize the department and bring order to this host-torn world. She is also slowly beginning to realize that in addition to sensing light and sound, she also has the ability to emit it, but she's not telling anyone.

Eileen has the ability to emit, detect, and absorb phenomena that exhibit mathematical wave behavior: sound and light. She uses technology to augment her abilities, relying on harmonics. The light and sound is emitted from her body (skin). Being inherently able to solve complex mathematical wave equations, she is blessed with a very high intelligence.

• Sound Wave Emission/Reception: Eileen can emit as well as absorb/hear audible sound as well as sound outside the audible range, allowing her to mimic voices, make herself completely silent, send out shockwaves, fire disorienting beams of ultrasound, produce the brown note, have superhearing, tell when people are lying, etc.
• EM Wave Emission/Reception: Eileen can emit and absorb/see visible light as well as light outside the visible spectrum allowing her to fire microwaves, create flashbangs, camouflage, have x-ray vision, night-vision, etc.

Any high intensity light (such as a laser, powerful flashlight, or the Sun) pointed at Eileen's exposed skin floods her visual cortex and is temporarily blinding and deafening. The same is true if she is exposed to an unfiltered blast of high intensity sound (or if some pinpoint ultrasound was pointed at her skin, like a dog whistle or pest repellent) the same effect would occur. This is why she keeps her lab operating in mostly low-light conditions and behaves like a vampire when walking outside. Also why she wears a protective layer of armor.