By day, Enduragirl was Christina Anna Polina; successful UCLA chemistry grad. Straight out of college, she began working for nano-tech giant, the MicroLife Corporation. From here, she furthered research in biochemical manipulation of the human genome. Christina was a stunning portrait of beauty: a 5’ 8” tall, white, leggy brunette, with piercing blue eyes and a firm C cup chest. Her all natural measurements checked in at an eye popping 42C-28-38. Christina was 28 years old and single, and had been running her division of research at MicroLife for two years. However, in all this time, no one was aware she was also the night-time crime fighter, Enduragirl

Christina had been through tough times growing up. She had grown up in a small town to a poor family. She focused on her studies, dedicated to make something of herself. As she got older and as the boys started to notice the girls, the other girls in her school teased her in gym class for her small and skinny frame, especially her smaller breasts. This further drove her into studying into how to not only be smart and successful, but also stronger and more athletic.

As high school progressed into college, Christina always kept to herself and her studies when she came across some older genetic development documents from the mid 40's Nazi Germany. Taking these documents, she discovered how certain chemistry can change the potential densities of muscle, tendon, and ligament tissues. The only issue was she couldn't afford to resources to pursue this idea, but she kept working around the thesis till she could. Once she got into MicroLife Corp, she was surrounded with people and resources that she could use to experiment with. Using herself as a guinea pig, she first developed a serum that worked upon her muscles. Though at the same time, she started at the local gym, her physique changed drastically and practically overnight. Though no muscle mass was gained, her tone increased dramatically and she was able to lift much more weight than ever before. She also was able to perform exercises, for what she could guess, indefinitely.

However, with her new tone came rigidness. So, in researching a way around this issue, she developed a second serum that made her entire body warp, stretch, and elongate at her will. She grasped so much control with it that she even was able to change her body density to something as strong as steel. What she didn't realize was that these second set of "powers" was more mental/reality warping abilities localized to her person, and simply thought it to be a by-product of her serum.

As a joke, she would even "stretch" her breasts to become a cup or two sizes larger, before she would go out in public, just to see the attention it would draw. However, that is when she also discovered a side effect of her self-testing. Upon entering a smoke filled bar, she began to feel her body tone disappear, and her breasts that she inflated to a 42DD began to droop within her bra. She also began to stumble as if she was drunk, though she hadn't a sip on anything. She immediately walked right back out of the bar. About a half hour later, the weakness began to fade and her body was back to normal. She had no idea what did that to her, but upon another day of work, she was able to identify the culprit.

She walked outside to get something out of her car and a couple of interns were standing outside having a smoke break. One of them was a girl that just never liked Christina, and upon her walking outside, blew a cloud of her cigarette smoke in Christina's face. Christina barreled over and coughed heavily as the two teenagers just pointed and laughed at her. The interns went back inside as Christina hunched over and used a bench to hold herself up. She never felt so weak and drained in her life. Christina always knew she hated cigarette smoke, but she never had any idea that it would affect her like that. She continued her day out work and noted this to herself.

Christina had always been a big comic book buff growing up, and had idolized Wonder Woman, Mr. Fantastic and Ms. Marvel. When Christina discovered that she had superhuman levels of endurance and strength, as well as an elastic body, she began to wonder about putting her powers to a “higher use”. She began to consider fighting crime as a hobby. She decided on a simple shiny body suit that covered her body, albeit, had a little "tease" to show off a little cleavage, to perhaps over-compensate for all those times in school when girls teased her about her chest back then. To hide her face, she wore large tech-specs that allowed her to have several forms of vision.

Christina’s career move into crime fighting was moved into high gear when her beloved grandmother was randomly murdered. The police didn’t have a suspect, so Christina designed a costume, and Enduragirl was born. In the ensuing months, Christina vigorously pursued evidence to try and find her grandmother’s killer. She would often don her new costume at night in her search; but alas, she was never able to find a suspect. However, during the course of her search, she would occasionally witness a crime, like a purse snatching or carjacking. If she was in costume, she would apprehend the suspects on the scene. Usually, the criminals were so astonished at the sight of Enduragirl in costume that they didn’t put up much of a fight. Once the suspects were apprehended, Enduragirl would usually hogtie the criminals, call the police, and then jet off just as the police arrived. Christina got such a rush from capturing criminals that she would often spend as many as three nights a week searching the city at night for crime. At first, there was a huge media blitz following the initial few criminals that she apprehended, and all the newspapers wanted to know who this new superheroine was. So Christina would usually take a break from appearing in costume from time to time, until the media frenzy died down. Then when she needed to feel the rush of busting criminals again, she would head out at night and search the city. From ages 24 to 28, when she occasionally ventured out to fight crime, she almost always quickly overwhelmed her opponents with her strength.

Her crowning achievement was when she was able to help capture a young and coming arms dealer, Evelyn Petrovich. Evelyn would later gain superpowers of her own and become a criminal and become an arch-nemesis of Enduragirl, especially after discovering Christina's weakness to cigarette smoke. Prior to Evelyn, only once did she even yield the upper hand in a fight. Once when she fought off three female gang members from sexually assaulting a young college student; one of the gang members surprised her from behind, and was able to attack Christina’s giant breasts for a few moments. Enduragirl was eventually able to ward off the gang member, and made quick work of all three of them.

It has been a few weeks since her last escapade, and Christina feels the urge to put on the Enduragirl costume and fight crime again.