All the Lisbon girls are the objects of the narrators' erotic fantasy lives, but fourteen-year-old Lux is the one who turns out to be the real deal. She's smart, beautiful, and more outgoing and independent than the rest of her sisters, but her sexuality is what distinguishes her the most. While Cecilia is like a disembodied spirit, Lux is lust personified.
Our first glimpse of Lux is sexually charged. When Peter Sissen was invited to dinner at the Lisbon house for helping Mr. Lisbon at school, he asked to use the bathroom and was directed to the girls' upstairs bathroom. He makes the most of the opportunity, snooping around in all the girly stuff you'd expect to find there. The jackpot? A (gasp!) used tampon in the trash. Suddenly Lux knocks on the bathroom door and told him she needs to get something "private." Peter rushes out the door to tell the other guys that Lux is "bleeding between the legs that very instant" (1.12).
Lux is sexy. She likes to tan herself in the sun wearing "the swimsuit that caused the knife sharpener to give her a fifteen-minute demonstration for nothing" (1.36). On the night of Cecilia's party and suicide, Lux doesn't disappoint:
She was the only one who accorded with our image of the Lisbon girls. She radiated health and mischief. Her dress fit tightly, and when she came forward to shake out hands, she secretly moved one finger to tickle our palms, giving off at the same time a strange, gruff laugh. (1.42)
Like all the girls, Lux bonded even more closely with her sisters after Cecilia's death, but even then Lux is bolder. She sneaks a ride on a motorcycle, and wears her skirts really short once she returns to school. She tries wearing makeup to church (mom makes her wash it off). She flirts with Chip Willard at school and has a stream of boyfriends despite her mother's prohibition on dating. She's good at finding ways to sneak off:
Lux's brief unions were clandestine […] and were consummated in the hot box above the auditorium, amid uncomfortable theatrical lights and cables […] and in the most daring rendezvous, in the station wagon itself, for the fifteen minutes Mrs. Lisbon stood in line at the bank. (3.31)
But all isn't well with Lux. Her dangerous liaisons are kind of, well, indiscriminate.
But the boys who snuck off with Lux were always the stupidest boys, the most selfish and abused at home […]. That Lux consented to meet them in the dells and thickets of our school grounds only showed too well her disequilibrium. (3.31)
What's happening to Lux? Sounds like equal parts sexual awakening and self-destruction. She finally attracts the attention of the school heartthrob, Trip Fontaine. Although he can have any girl he wants, he gets struck by lightning when he meets her. Trip says that she's:
[…] the most naked person with clothes on he had ever seen. (3.47)
Lux has no idea of her effect on him, but he's obsessed. He finally makes his move and she kind of responds. After a chaste visit at her house under the watchful eye of Mr. and Mrs. Lisbon, he's getting into his car, when:
Suddenly the air inside the car churned. He felt himself grasped by his long lapels, pulled forward and pushed back, as a creature with a hundred mouths started sucking the marrow from his bones. She said nothing as she came on like a starved animal. (3.57)
Once Lux's sexuality is unleashed, she's insatiable. Trip, talking to the narrators later in his drug-addled life, says he's never gotten over her even though he's had scores of women.
Years later, he was still amazed by Lux's singleness of purpose, her total lack of inhibitions. (4.58)
Her parents probably caught her, because Lux was grounded and Trip banned from the house. Lux tried to rebel in other ways. She forges excuses to get out of gym class, and climbs up on top of the lockers to smoke. Her smoking buddy Julie has a theory:
She did say that Lux had an affected hardness that might have been a reaction to pain. "She was always saying, 'Fuck this school,' or 'I can't wait until I get out of here.' But so did lots of kids." (3.76)
Julie would sometime find Lux lying on top of the lockers, hugging herself and shaking. Eventually, she seems to feel better and be more involved at school, singing and dancing in the school musical. Trip decides it's time to make a move, but Mr. Lisbon says no way can he take Lux out in a car. He convinces the Lisbons to allow all the girls to go to Homecoming as a group. It's the only way he could see Lux.
Lux is ecstatic. She hugs and kisses her dad like a little girl. Her sisters go along with the plan just to please her. And she has a great time, sneaking smokes, hanging out with her sisters, finally slipping away to make out and drink with Trip under the bleachers. She tried to make the most of the night:
Lux found a way of arching her back that made her [baggy, homemade] dress tight in front. (3.177)
And guess what—she and Trip are crowned Queen and King of the prom. So things are going great for Lux, right? Wrong. Lux disappears with Trip, and the girls go home without her. Two hours later, and way past curfew, Lux arrives home in a taxi and her dad starts to drag her into the house; her mom almost slaps her.
Later the boys learn that she and Trip had sex on the football field, and Lux started to cry, saying she always screwed things up. Trip abandons her, which is why she has to take a cab home. It's the beginning of the end for Lux.
The prom night disaster results in a total lockdown in the Lisbon house. The girls are pulled out of school and not allowed to leave the house. Mrs. Lisbon makes Lux throw all her rock records into the fire. Not long after, Lux begins having sex with random men on the roof of her house. No one knows how she meets them, since she never leaves the house, but her nighttime activities serve as the narrators' sex education, watching Lux through binoculars.
Some of the boys who claimed to be her lovers said that Lux looked really skinny; she had cold sores and was missing patches of hair. Despite that, she was sexually ravenous:
We got an idea of her state of mind from the little that got back to us of the little she said. She told Bob McBrearly that she couldn't live without "getting it regular," though she delivered the phrase with a Brooklyn accent, as though imitating a movie. A sense of playacting permeated much of her behavior. Willie Tate admitted that, despite her eagerness, "she didn't seem to like it much," and many boys described similar inattention. (4.14)
Lux is clearly getting desperate. There's an empty, sad quality to all this sex. She meets her lovers in the dead of winter; the boys think she's deranged. She has some bizarre birth control measures that involve a bottle of Coke or vinegar when she can't get real contraceptives. At one point, she has to fake a burst appendix to get the ER so she can have a pregnancy test. She's not pregnant, but she's gotten HPV.
Dr. Hornicker, the psychiatrist talked with her and though Lux denied it, he saw how depressed she was, and decided that all the surviving Lisbon girls were suffering from Post-Traumatic Stress Disorder (4.60). Years later, Dr. Hornicker said that Lux's "promiscuity was a commonplace reaction to emotional need" because of the lack of love in her household (3.60). That sounds a little too simple for us.
The boys don't see any of the sisters until they start sending secret messages to them. Lux put a letter into Chase's mailbox saying she was so over Trip; other letters arrived, hinting that the girls wanted to escape. Lux meets the boys on the night they set to make their getaway, telling them to wait while her sisters "pack."
While the rest of the girls are in various parts of the house killing themselves, Lux distracts the boys who think they're coming to rescue them from their prison. She uses her sex appeal that keeps the boys from noticing that anything is off: she undoes Chase Buell's pants:
Even though she was doing it to Chase Buell, we could all feel Lux undoing us, reaching out for us and taking us as she knew we could be taken. (4.195)
She goes into the garage, saying she'll wait for them in the car. The police find her dead from carbon monoxide poisoning. Lux, as she often was, was a master manipulator that night:
She had escaped in the car just as we expected. But she had unbuckled us, it turned out, only to stall us, so that she and her sisters could die in peace. (4)