Léon, a boarder at Monsieur Homais’s house, meets Emma upon the Bovarys’ arrival in Yonville.
Emma and Léon chat it up all night, and the young man is flattered and infatuated with the doctor’s wife.
Léon has never experienced this kind of intimate conversation with a woman, and he’s fascinated by Emma.
After the birth of Emma’s child, she and Léon take a walk to visit the baby (who’s staying outside town with a wetnurse). The town is scandalized by how much time the two young people spend together.
Emma and Léon are totally BFFs. He gets her little gifts like houseplants, and in return she has a beautiful blanket sent to him.
Léon is head-over-heels in love with Emma, but he’s too scared to do anything.
Emma realizes that Léon is in love with her, which in turn makes her fall in love with him. She focuses all of her fantasies on him. However, in an attempt to turn her thoughts away from adultery, she tries to play the part of the virtuous good wife.
Everyone is fooled by Emma’s act, even Léon. Depressed and emotionally frustrated, he decides to leave for Paris earlier than planned. He pays Emma one last visit, in which he doesn’t declare his love – instead, he makes a big show of saying goodbye to little Berthe.
Léon heads off to law school in Paris for a couple of years, during which we don’t see him. We learn later that he spends a lot of this time playing around with the ladies. He’s a different man when he gets back.
After his studies end, Léon moves back to Rouen.
In Rouen, Léon has a chance encounter with Charles and Emma at the opera.
Upon their reunion, all of the old feelings come rushing back again. Léon convinces Charles to let Emma stay in Rouen for an extra day to see the end of the opera (they left early).
The next day, Léon goes to see Emma, after confirming that Charles headed back to Yonville. He visits her in her hotel room, where they talk openly about their feelings for the first time. However, both of them paint a deceptive picture of their time apart – Léon doesn’t mention any other women, and Emma doesn’t mention Rodolphe.
The couple meets at the famous Rouen cathedral the next day. Emma is resolved to break off their affair before it even starts, but Léon has other ideas. After a hectic tour of the cathedral, they get in a cab.
We don’t see what happens in the cab, but we can imagine. They force the poor horse and driver to run around town all day so that they can have clandestine conversation (and other activities) in the secluded carriage. By the end of the day, they are clearly a couple.
From this time on, Emma and Léon are an item. She comes to visit him in Rouen every week, and he even comes to visit in Yonville.
In Rouen, the couple has a specific room at the luxurious Hôtel de Boulogne that they rent every Thursday. Emma pampers her lover, who basks in her attention.
Léon gets in trouble at work for missing so many days because of Emma’s visits. He keeps bowing to her whims, however, and skips out on work for her. He even does silly things like dress all in black and copy out love poems for her. He’s confused by her wild behavior, but still intrigued by her.
One day, Monsieur Homais comes to give Léon a surprise visit. Unfortunately, it’s on one of Emma’s Rouen days. The pharmacist irritatingly follows Léon around and prevents him from meeting Emma. In a huff, she leaves.
After the Homais debacle, things start to slow down. Both Emma and Léon lose steam, and their affair gets less exciting. Léon starts to become less and less interested in Emma’s affections.
Emma keeps working at the relationship, hoping to feel something more exciting and genuine by throwing herself at him. Léon resents her dominant attitude, but she still has control over him.
Léon begins to wonder if his mother (who heard a rumor about his mistress) and friends are right – should he get rid of Emma?
Léon and Emma go to a masked ball with some of his friends, then spend all night partying. Emma realizes that she has sunk to new lows – all of Léon’s pals are out with prostitutes.
Léon and Emma are through. However, she does come and ask him desperately for the money she owes Lheureux. She attempts to force him to steal money from his office to give to her, or to take out promissory notes of his own. Léon says no, but lacks the will power to flat out refuse her. He half-heartedly goes out, but returns empty handed. Finally, to get rid of her, he tells her that a rich friend is coming back to town that night, and that he will meet her in Yonville the next day with the money. It’s obviously a lie.
Léon doesn’t show the next day.
After Emma’s death, Léon ends up marrying someone else, and settles down to a quiet life as a notary in another town.