Lisa was the last of two children born to a wizard couple - Jonah Knotley Jr. and his wife, Ingrid. Despite the love every member of that family wanted to have for one another, there was never much time for bonds to strengthen - starting with Ingrid, whom perished to Dragon Pox when Lisa was just a very small child.
This shook the family to the core, and their living situation didn't make it any easier. There was some money saved, so Lisa's brother was enrolled in Greyheme; the father was an Auror, and so he had to incur risks at work; and Lisa, well, she was left to a babysitter most of the time. The girl hardly had any sort of communication with people until she enrolled in Penrose.
Much like her brother, she was forced to stay in the dormitories. She became all too attached to her dorm roommate out of starvation for social interaction, and eventually they developed a secret romantic relationship. However, it all came to an end during the break between third and fourth years. Her father had perished in the line of duty and her brother had to fend for them both, being of age at that point. With dwindling resources Lisa was pulled out of Penrose, but not before altering her girlfriend's memories so to forget her being much more than just a simple roommate, wanting to protect her from the pain of loss she herself was enduring.
She was enrolled in the public school of Tallygarunga immediately after. Once again she grew attached to her roommate, albeit not in a romantic manner - it was just someone whom helped her deal with her grief. This grief slowly morphed into the realization that life was too short and you should leave nothing you wanted to do behind, as you didn't know when the rug was going to be pulled from under you just like it had happened to her parents. She became absolutely obsessed with success, and her once amiable disposition endured a brutal change.
Of course, that didn't come without a price. Her house mates didn't want someone like her to become the potential successor to the House's Dueling Club's Captain position, which was about to go vacant with the graduation of the current one. To thwart her very obvious plan to succeed this person, the team declared she would only be considered if she were to defeat her best friend in a duel - surely that would stop her, right?
Wrong. Without a shred of hesitation, she did so - even more than that, she did so in brutal fashion, so to make a point. True to their word, they considered her and eventually gave her such a position; but her friend never forgave her for the humiliation. She asked to be transferred out to another room, leaving Lisa by herself and never speaking to her again.
It took her a long time to start regretting her actions out of pure denial that what she did could be considered a failure. She effectively failed her friend and was unable to prioritize things. As school goes on, she finds herself having a hard time juggling her extreme variant of ambition with the need to make up for all her past mistakes. She needs guidance, but she isn't sure where to get it from anymore, given the amount of bridges she's burned at this point.