The Wrong Way to Use Healing Magic

Ordinary high school student Usato is suddenly summoned to another world with Suzune, the student council president, and Kazuki. They are tasked with saving the Llinger Kingdom as heroes, but Usato was summoned by accident. Everything changes when Usato's healing magic talent is discovered, and Rose, the Rescue Squad captain, takes him for intense training.

Usato, now a member of the Rescue Squad, immediately begins his hellish training with Rose. Just when he lets his guard down after finishing his first day of training, he is forced to do nothing but run. As Usato continues to train while Rose heals his sore muscles with magic, his body gradually begins to change.

Thrown into the monster-infested "Darkness of Llinger" by Rose, Usato tries to survive as he attempts to hunt a Grand Grizzly. At first, Usato is overwhelmed by the Grand Grizzly. However, as he continues to observe it, he gradually grows attached to it. A few days later, when Usato finally resolves to kill the Grand Grizzly, he witnesses a horrific scene.

Usato learns that war with the Demon Lord's Army is near and doubts he can fight like Rose. Training with Blurin, a Blue Grizzly cub he found in the "Darkness of Llinger," he meets fellow healer Orga in the castle town. After their chat, Usato becomes more determined as a member of the Rescue Squad.

Usato is assigned to accompany Suzune in her training. However, together with the knight Aruku and mage Korin, they encounter bandits. While they are able to fend off the bandits without much difficulty, a horde of Fall Boars attack. Usato and Suzune are blown away into the "Darkenss of Llinger" and are forced to survive in the wilderness.

Usato and Suzune report their safe return from the "Darkness of Llinger" to King Lloyd. Sensing something amiss from the unusual monsters, King Lloyd orders Rose to scout the area. Rose discovers the Demon Lord's Army preparing for invasion. Meanwhile, Usato visits Orga and Ururu's clinic and joins them at an accident scene.

Usato is puzzled by the disturbing visions shown to him by the beastman girl Amako. At night, when he is unable to sleep because of his concern, mysterious balls of light appear outside his window. Lured by the balls of light, he looks outside and sees Kazuki. Kazuki begins to share his feelings with Usato, admitting that he is afraid to stand on the battlefield as a hero.

Five years ago, Rose, a battalion commander of Llinger Kingdom, led an eccentric unit, including her second-in-command, Owl. Ordered on a reconnaissance mission into the "Darkness of Llinger," Rose and her team reaffirm their bonds. The next morning, they encounter a mysterious group of demons transporting monsters, including one with an unusual aura.

Rose's men and the Demon Lord's Army cross swords in the "Darkness of Llinger." Just as Rose and her men manage to gain the upper hand, Nero, a general of the Demon Lord's Army, orders his own men to attack without concern for their own lives. One by one, Rose's men are killed as they take each other out. Nero continues to attack Rose, who is fraught with anger and has lost her composure.

The war against the Demon Lord's Army has begun. Usato treats the wounded, witnessing the battlefield's harshness. As the war progresses, Usato and Rose move to the front lines. Using his well-trained abilities, Usato saves the kingdom's knights amid the enemy onslaught. Meanwhile, Suzune and Kazuki, fighting as heroes, face a mysterious demon known as the Black Knight.

Suzune and Kazuki are defeated by the Black Knight, who can "reverse" attacks. As the Black Knight is about to finish them off, Usato's timely punch hits its face, causing damage. Uniquely, Usato's attacks bypass the Black Knight's "reverse" ability, inflicting consistent damage. This is due to Usato's unconventional use of healing magic.

The Llinger Kingdom decides to interrogate the captured Black Knight for the next battle. The Black Knight demands to meet Usato before agreeing. Usato visits the prison and notices the Black Knight's injuries, healing them with his magic. Healed by Usato's magic, the Black Knight then...

Amako, who informed Usato of Suzune and Kazuki's danger, now wants Usato to save her mother. Then, he finds out why Amako came all the way from the Beastlands to the Llinger Kingdom. Amako asks Usato to accompany her to the Beastlands, but he is unable to come to a decision due to his position as a member of the Rescue Squad. After some thought, Usato finds a way to go to the Beastlands.