Along with her club's gear which is always by her side, Rico sports a platinum blonde hair along with her thin oval glasses. She also wears a pair of green and white gym clothes with her name on them.
As the president of the Wall Cleanup Club, she sees it her duty to keep the Walls of the school in good condition and well guarded. Rico dedicates most of her time into maintaining the Walls against the Titans, illustrating that she is a focused student and upperclassman.
After Eren and the gang were designated to another club, Rico warmly welcomes the group to the Wall Cleanup Club as a part of her introduction. Rico explains the main statistics of the club being originally up to a hundred members but at this moment she is the only one left. As Jean comments on the basic purpose of the club, Rico attests that they can choose any club they want, leaving out the exception of human clubs which are already full. With that said, Rico orders them their first task; clean all the windows on the new building.
On Jean's attempt to escape, Rico is on guard and takes him down. She introduces the club's secret weapon to the gang, the omni-directional mobility gear. She demonstrates the uses of the gear, mainly for cleaning the Walls. As Eren and Jean fight over the device, she remarks their childish behavior. In order to close the group's anticipation, she pledges to teach them only if they finish their given task. Moments later, Rico nags about the group's determination for the gear only to be greeted by a dazzling gleam coming from the cleanness of the windows. Fascinated by the group's output, she fulfills her promise.
Disappointed with Eren's repetitive failure, Rico suggests that if he does not know how to use the gear, he would have to leave the club. With Armin deducing the gear to be broken as the cause of Eren's failure, Rico denies it and explains the history of the mechanism. Rico declares that if she finds a single flaw in the gear itself, she will eat spaghetti through her nose. Up until a busted spring on Eren's gear catches her attention. Mikasa threateningly asks her about the truth in Armin's deducing, scaring Rico. She tries to uphold Hannes as he tries on Eren's broken gear causing the adviser to trample onto Jean. Luckily for her, Hannes' drunkenness covers up her faithful trust on the gear's condition. Rico adjourns the activity and proceeds to get the gear fixed.
Rico hides the damaged part of the gear as she, along with the first years, rejoice on Eren's successful attempt. As Sasha senses a tremble on the ground, Rico instructs the group to take cover as she tells the sole purpose of the Wall Cleanup Club. Watching as the Titans horribly vandalize the Walls, she tries to stop a raging Eren from lunging into an attack, asking if anyone taught him how to use the gear. Eren then fails due to running out of gas, and Rico disappointingly says she has to teach from the start.
In the morning, Rico angrily demands an explanation of why Jean has been skipping the club's activities, and he replies that he had been busy attending various other activities, with Eren saying that he knows that Jean is not doing any of them. A furious Rico then bears the entire class responsibility and orders them to clean every window in the school.
Following a challenge by Levi later that day, Rico participates in the school's Sports Day games. In the ball-tossing game, Rico effectively dodges and deflects all balls tossed at her. When she sees Jean cheating by using the club's gear, she angrily deflects a ball towards him, before he is hit by a barrage of balls. Rico's team then surrounds Jean and beat him up at her signal.
In the last game, shoulder wars, she commends the first years after they take one of her grade leaders' bandana and is then commanded by Ian to handle an opposing Year 1 team in the rear. Rico and her classmates later come to help the first years with cleaning.
Following a student council scandal, an election for a new president is held and Rico aims to win in order to increase her club's budget. When the other candidates start chasing after a notebook that allegedly contains info which could help them win the election, Rico joins the pursuit. Using her club's gear, she intercepts Eren as he jumps to catch it and kicks him in the face, before grabbing the notebook. As she reads the notebook, Rico reveals that it merely has cleaning tips.
When it is time for every candidate's final speech, Rico goes first and says in order for her to make the school cleaner, she plans to force all students to clean during each break, after school, and volunteer cleaning on non-school days. The whole hall starts booing, much to Rico's shock.
In the school's 104th festival, Rico, along with Ian, participate in the gourmet competition serving kamemashi. Rico arrogantly assures Eren, who is running a cheeseburgers stand, that they will be winning the competition. As they are about to open their rice pot's lid, Eren's chee-burgs stand draws more customers by advertising double cheeseburgers for the same price. Rico commends the first years, then tells Ian to open the lid, but everyone is interrupted by loud trembles in the ground caused by a horde of Titans approaching, and ultimately stealing all of the food stands.
When Eren and the others venture into the Titans' building, Rico and Ian await them at Hannes' office, having brought with them the club's gear. Accompanying them to the principal's office, they find a key and a door inside a walled town. Ian warns them of approaching Titans, and everyone distracts them while Eren pulls the key. As one last Titan stands in Eren's way, Rico charges forward and hits its eye with a spoon. A tearful Rico is relieved once Eren manages to open the door.