Keyaru is the main protagonist of Redo of Healer. On his 14th birthday, he was chosen as one of the Heroes, the Hero Healing.
After years of torture at the hands of his own allies, he manages to break free and get the Philosopher's Stone. He then uses the item to go back four years time to exact revenge against the people who tortured him.
Pre-Betrayal
Initially, Keyaru was a very kind and gentle boy with dreams. When he discovered that he was one of the Heroes who would save the world, he was very excited but he was afraid to use his power when he found out that by healing people, he absorbed their memories and pain.
Post-Betrayal
After being betrayed, imprisoned, drugged, tortured, beaten, and raped by several people who wanted to break their level limits for a long period of time, Keyaru's kind personality changed completely to that of a man vindictive, cruel, brutal, unstable, psychopathic, relentless, bloody and sadistic. Because his naive personality was what allowed him to be exploited, Keyaru replaced his old personality with that of a manipulative and cunning misanthrope.
One of Keyaru's redeeming factors is that he has no desire to harm those who have done him no harm, and in fact makes it a personal rule not to drag them into his revenge. Keyaru also has some sympathy for people who strive for justified revenge the same way he does, and will do his best to help grant them their desire with the condition that they also help him with his.
It is quite difficult to interpret how he really feels about the girls in his party, as he refers to them only as yours "toys," in his inner thoughts. This implies that he does not really love them and only sees them as simple tools; however, apart from that and some relatively minor things, like making Freia carry his luggage as a form of revenge for having used him as a pack mule, he treats them only with kindness, in total contrast to his own treatment at the hands of the Flare party. Keyaru has also shown himself to be genuinely enraged whenever any of them are injured, but it is not clear that it means that he is more protective of them than he can realize himself, or if he is just simply possessive.
Keyaru has also confessed once that during his travels with his party, even if only sometimes, his thirst for revenge vanishes, but he disregards this when he remembers that she still has people to get revenge on. But this may be an unconscious way for him to refuse to acknowledge that he is starting to care about other people, out of fear of losing them too.
Previous Timeline
As he was one of the chosen heroes, Flare Arlgrande Jioral took Keyaru from his village to Jioral Kingdom, where he identified himself as the Healing Hero.
Unfortunately for Keyaru, prejudice against the healer class resulted in Flare, the Heroes and Jioral Kingdom abusing and torturing Keyaru to the point where he was addicted to a healing drug Flare fed him to keep him in line. While Traveling with Flare, Blade, and Bullet, he was often sexually and physically abused by all three. Developing an immense hatred toward them, he eventually develops a resistance to the drug and is able to maintain his sanity.
However, as he was aware that he would be unable to take any of the heros in a fight, he kept quite and pretended to still be dependent on the drug
When the heroes are incapacitated by the current Demon King, Keyaru is able to defeat and reveals him to be a silver-haired woman. Using the Philosopher's Stone he obtained from her, Keyaru declares vengeance on Flare before reversing time by four years.
Current Timeline
After waking up in his village, Keyaru obtains the ability to read statuses of other from the spirit of the stars. Over the next several months, he eats numerous toxic mushrooms every day to develop his poison resistance. Eventually, Flare comes to his village and Keyaru reveals himself as the Healing Hero. She then takes him to the royal capital of the Jioral Kingdom.
When he is called to restore Kureha Clyret's arm, Keyaru pretends to faint to get a look at Flare's reaction. Later, Keyaru is given a cup of drugged tea by Flare and after he drinks it, he falls unconscious. He later wakes up chained in a prison cell. In confinement, Keyaru is raped by soldiers who want to increase their level cap.
Keyaru escapes his prison cell after one month of captivity. After transforming to the Knight Captain by beating him on combat battle, he turns "Keyaru" in and asked to speak to Flare in her chamber. Killing her attendants a with a technique stolen from Kureha, he then proceeds to torture Flare.
To complete his revenge, he transforms her appearance to suit his taste and erases her memories. After arriving at an inn with Flare, he changes his appearance and adopts the name Keyaruga. He then convinces the amnesiac Flare that she is his slave and lover, Freia, before the two have passionate sex.
Keyaruga and Freia make their way to a village ravaged by a plague. Realizing that the illness is originating from the water, Keyaruga creates an antidote which he sells to a merchant. He then proceeds to use the money to by an ice wolf slave, Setsuna, who agrees to serve him in exchange for his help to get revenge of the people who attacked her village.
Powers and Abilities
Heal: By healing things and concepts, Keyaru performs various abilities from the Healer Class
Recovery: By manipulating time and matter, Keyaru can return things to their original states and heal deep injuries from himself or others. Initially, using it to heal someone would cause him great pain, but later on he learns how to use this skill without showing any signs of pain at all.
Imitation: Every time Keyaru heals someone, he gains the fighting skills and experience from that person. He already used this skill many times before, retaining all the knowledge from different fighters, soldiers and mages.
Predator: Can either absorb or copy some of the levels of a person, allowing Keyaru to level up. The same ability can also be used to absorb all the mana from someone, or just a portion if he wants. If the target is a mage or fully dependent on mana, that person gets incapacitated and weakened.
Corruption: Destroys the target from inside by corrupting them. Keyaru usually refers to this ability as a One-Hit KO skill.
Upgrade: Ability that allows Keyaru to modify things by "upgrading" them to a desired state.
Superhuman Augmentation: By upgrading himself, he can change his stat spread by enhancing some stats (such as strength, speed, magical defense, physical defense, and magical attack) at the cost of reducing others. He cannot, however, change his stat total.
Transmutation: This allows him to change an individual's appearance, physical stats and mind.
Memory Erasure: While touching someone's head, Keyaru can change the memories of an individual and can also erase them at will. He can also force the target to experience memories, as shown with Kureha Clyret.
Shapeshift: By using Upgrade on himself, Keyaru can change his appearance.
Rewrite: Keyaru can use Upgrade on enchanted/magical objects, changing their functions.
