When Hajime Kanzaka was in high school, he created a story where Lina was a 10-year-old clone of her now-older sister, Luna Inverse. In this story, Lina was obsessed with machinery. When Kanzaka began writing Slayers, he made Lina five years older and obsessed with magic instead of machines. Rui Araizumi claims that Lina's design was based on a young Audrey Hepburn.
In the first part of the Slayers series, Lina informs the audience that she is 15 years old. As the series progresses, she grows older. Regarding the anime, a good rule of thumb is to remember that in the first series, she is 15, in Slayers NEXT, she is 16, in Slayers TRY, she is 17, and in Slayers Revolution and Slayers Evolution-R she is 18. Her age is more difficult to determine in the novels and manga series. She is 15 years old in the first novel, then 16 in the third novel, taking place a couple of months later. According to the official data-book Slayers Reading, the twelfth novel takes place 2 years after the first. That means she is 17–18 years old during the first part of the second story arc. She is understandably younger (around 13 or 14) in the Slayers Special series. Her height has been said to be 147 cm (4 feet 10 inches).
Lina is known as one of the most powerful and feared sorceresses in all the land. By the age of 14, she had already become famous. Despite her bad habits of eating too much (justified by her serious magic usage, a characteristic she shares with Pokota) and taking money from bad guys, she has good intentions. Most of her bad nicknames such as Dra-mata, Robbers' Killer, and The Enemy of All Who Live come from the fact that she often causes plenty of collateral damage when fighting the forces of evil. Lina is a member of the Sorcerer's Guild, and her assigned mage color is pink (Official title: Lina the Pink), much to her embarrassment. At times Lina appears to be fearless, but there are (at least) two things she is afraid of: Luna and slugs. She is also uncomfortable around fishmen, such as Noonsa and Rahanimu.
Lina self-dubs herself as a "Magical Genius" but she isn't at all exaggerating. She specializes in black magic, yet she is also skilled in shamanism, slightly versed in white magic, and can also hold her own with the short sword. Lina has an extremely high magic capacity, and she is able to draw upon indescribably powerful spells such as the Ragna Blade and Giga Slave. When she acquired the Demon's Blood Talismans from Xelloss, she was able to increase her magical capacity even more, giving her the ability to cast more powerful spells more often. However, even a single Ragna Blade can drain her of all energy. Lina has used Giga Slave four times. The first time she tested it, she turned a body of water into a sea of death, where no life would grow. The second time was when she summoned it into the Sword of Light in order to defeat Ruby Eye Shabranigdu, and in NEXT, when she intended to defeat Hellmaster Phibrizzo. However, this time, the Lord of Nightmares possessed Lina's body and used it as a medium for destruction. Lina almost cast the Giga Slave in TRY to kill Dark Star Dugradigdu, but she was stopped by Sirius and Erulogos. And finally, she used the spell once again to defeat the ghost of Shabranigdu in EVOLUTION-R.
In addition to battle skills, Lina is also a master businesswoman. This is to be expected, as she grew up in a family of merchants. She tries to get the best bargain on everything, and when she does not get her way, she gets violent, often pressuring people into selling (or even giving) her items.
Lina's parents own a grocery store in Zephilia. Her father is an ex-mercenary and her mother an ex-sorceress. According to Kanzaka, Lina's grandparents died before her birth. Her older sister, Luna Inverse, is a Knight of Ceifeed, and she works part-time as a waitress. Lina is terrified of her sister to the point of hysterics, and she probably deserved these feelings. When she was younger, Lina wanted to make money, so she sold projections of Luna bathing, and as a result, Luna punished her. It has been said that Lina started training to be a sorceress as a result of an inferiority complex to her sister. Nevertheless, Luna was the one who suggested Lina go out and explore the world. Lina's father ran into Gourry several days before Lina herself did. During this time, Gourry was considering discarding the Sword of Light as it had caused nothing but trouble between his immediate family members, but Lina's father managed to convince Gourry to do something worthwhile with the sword, in part ultimately causing the two eventual constant companions to meet. Lina is thus far unaware that the two have met.
Lina's initial impression of Gourry Gabriev was not too great. While she did find him physically attractive, his lack of intelligence and tendency to treat her like a child quickly became an annoyance. Over time, however, she became attached to him, and they became the best of friends and partners. Gourry is supposed to protect Lina, when in reality, they both look after each other. They share a mutual understanding that goes beyond the means of conventional friendship. Throughout NEXT, Lina found herself becoming increasingly self-conscious and flustered around Gourry, especially when he would do something nice for her, and by the end of NEXT, she realized she was in love with him. This love was shown to be reciprocated at the climax of NEXT, when Lina was possessed by the Lord of Nightmares after losing control of the Giga Slave she cast in order for Gourry's life to be spared. Gourry subsequently dove into the Sea of Chaos after Lina's possessed body exclaiming that he needed her, and she was ultimately returned to her human form. The two shared a kiss while still within the Sea of Chaos, though it was promptly forgotten by both of them when they were returned to their world, the only reminder being the memory that "something important" had happened. In all incarnations of the series, the "romantic" aspect of their relationship is addressed very little, if ever at all, mostly due to Lina's immaturity on such subjects (and in reality, the fact that Hajime Kanzaka himself stated that he was poor at writing romantic scenes), but it is always clear that both of them share a strong connection and a unique bond. In the end of the novels, Lina and Gourry traveled back to Zephilia together, with Lina thinking that he wants to meet her parents so he could propose to her. In the anime the pair continue to travel together to whatever adventures the winds may take them.
Lina and Zelgadiss Graywords are able to respect each other as both good friends and allies. They both share some of the same battle instincts and skills, and they help to keep each other in check. Lina forces Zelgadiss to get up and do things, while Zelgadiss forces Lina to calm down and pay more attention to what's going on around her. They are nearly equals in intelligence, and as a result, they are able to hold intelligent conversations when everyone else is going crazy. However, Lina gets easily fed up with Zelgadiss's low self-confidence and pessimism, and in turn, Zelgadiss hates Lina's quick temper and bad habits.
When they first met, Lina thought Amelia Wil Tesla Saillune was annoying, and she wanted to ditch her as soon as possible. Eventually Amelia proved she could be useful and more than just a tagalong, and Lina accepted her as a friend and companion. They share an almost sister-like relationship, showing affection at some times, and jealousy and irritation at others. One thing is for certain: Lina is envious of Amelia's physique. She does not think it is fair that a younger girl has a more developed body than her. (It should be noted that, in the novels, Amelia is said to be the same age as Lina, while in the anime, she is introduced as one year younger.)
Lina and Naga the Serpent's relationship is certainly strange. One day, Naga appeared before Lina, declaring herself to be Lina's greatest rival. Ever since then, they have shared a love-hate friendship and rivalry. Sometimes they are on opposite sides, but most of the time, they work together. Lina often gets annoyed with Naga's over-confidence and tendency to overlook important facts, and in return, Naga teases Lina about her short stature and underdeveloped body. It is not known why they parted ways, but Naga was the one who told Lina to travel to Saillune to meet a prince. Unfortunately, Lina didn't realize who exactly this prince was, and in the end, Naga got the best of her.
Lina and Xelloss share a mutual respect, not a friendship. Each knows the other is capable of utterly destroying him or her if given the chance, so they both have a sort of truce with each other. They help each other, but only when their interests overlap. Xelloss often gets the best of Lina, using her greed or quick temper to his advantage, and she usually gets her revenge. The fact that Xellos seems to know everything but never wants to tell anything perhaps annoys Lina the most.
Lina feels sympathy for Sylphiel Nels Lahda, and she tries her best not to become annoyed with Sylphiel's shy and reserved nature. Despite her intelligence, Lina is not fully aware of Sylphiel's attraction to Gourry, or at least she pretends not to know so that no feelings are hurt.
Lina's relationship with Martina Zoana Mel Navratilova is bizarre and varied. Lina destroyed Martina's kingdom, and as a result, Martina became intent on getting revenge, doing everything from putting curses on Lina to messing her up at every possible opportunity. Lina saw Martina as an annoyance that had to be dealt with. In the end of NEXT, Martina helped Lina realize her feelings for Gourry, and the two of them became somewhat closer to being friends.
When Filia Ul Copt came to Lina asking for help, Lina did not understand why she, of all people, was being chosen as the representative of the human race. She was initially annoyed with Filia's way of "testing" her power (attacking a port during an important delegation). Throughout TRY, Lina and Filia were often irritated at each other, but they still worked together despite their differences. Lina helped Filia to see the truth in the world, and they got along well by the end.
The relationship between Pokota and Lina is an interesting one. They are both serious magic users with similarly huge appetites, and are similarly sensitive to teasing from others, especially from each other, which results in frequent fireworks from the two. However, that very similarity enables them to connect with and understand each other, and ultimately they became friends. However, their friendship sometimes seems to be more akin to that of a mentor-apprentice relationship.
Witnessing her abilities and deeds firsthand, and also due to the friendship between Lina and Amelia, Philionnel respects Lina and treats her as an equal, and she usually does the same; although Philionel and Amelia's behavior are so alike that she sometimes feels uneasy with both of them together. When Saillune was attacked by Zanaffar in Slayers Revolution, Philionel trusted Lina with the defense of the city.