Trapped in a Dating Sim: The World of Otome Games Is Tough for Mobs.

Leon is reincarnated in the world of the "otome game" he was playing as the third son of an impoverished baron. While he's trying to find happiness as a "mob" or background character, he's offered a terrible marriage proposal.

Leon officially begins attending the academy. Though the romantic interests he saw in the game are present, for some reason the girl with them is not the protagonist of the otome game, but a girl he doesn't recognize. Leon feels there is something off about the situation...

Marie is being bullied by Angelica's followers. Because events don't match what happened in the otome game, Leon attempts to gather information on Marie.

Leon's Armor Arroganz is mocked for being old fashioned, and the weapon Luxion has prepared for him is... a shovel! The audience ridicules Leon, but will he be able to defeat his five opponents?!

Leon's duel against Julius and his kingdom's best Armor begins. Why does Julius choose Marie over Angelica? His feelings drive him to attack Leon...!

Leon and his friends open a cafe at the school festival. However, Julius' posse open their own cafe, and a mysterious girl trying to get close to Leon appears before Olivia. It looks like there's trouble ahead at this school festival...!

Jilk appears in the bike race held on the final day of the academy festival. However, he is obstructed by the followers of his ex-fiancee and is badly injured. The situation develops further, and Leon finds himself dragged into it...

Olivia finds herself pushed into a corner by Stephanie. Meanwhile, while understanding Olivia should resolve the pirate hunting situation, he chooses to prioritize efficiency and gets involved.

Leon's attempt to support Olivia backfires. He attempts to clearly define their relationship as one between mob and protagonist, but... Meanwhile, during a sword fight against Brad, he realizes the difference in their resolve.

The school trip begins, and Leon heads to the southern island where the item he seeks can be found. Once there, he runs into Angelica and Olivia at a shrine dedicated to marriage while things are still awkward between them.

Leon weaves his way through the horde of monsters alone in order to rescue Angelica. Meanwhile, Chris and Olivia battle fiercely alongside the other students on the passenger ship, but they're surrounded by the duchy's fleet...!

Leon rescues Angelica and repairs his relationship with Olivia. He defeats the enemy's Armors one after another to crush the duchy's will to fight, but then the duchy's strongest hero, Vandel the Black Knight, appears.