|“||I'm sure that as long as you're kind and just, and have a strong heart, you'll be able to stay human, even if you become a monster. It's all about not being a demon on the inside!||”|
|— Yuki, Scale Shield|
Yuki (ユキ Yuki) is a friend of Teppei Ushizume.
Yuki appears to be a rather upbeat and cheerful person, happily greeting Teppei when he was a stranger to her and was kind enough to save him from internal combustion. She also seems to be very inquisitive, as Teppei remembered her bombarding him with questions about himself and his journey.
Yuki is an average sized young girl with short, dark-colored hair that reaches down to the nape of her neck. Her usual attire consists of a round, light-colored hat with a dark stripe running down the right-hand side of it, a scarf, a light-colored jacket with dark buttons, dark-colored pants, and light-colored boots. Underneath her jacket, Yuki wears a collared shirt with a dark-colored tie.
In her fully transformed state she takes the appearance of a humanoid rabbit, complete with fur and tall, pointy ears. Her fur is light-colored, and covers all of her body, with it being gathered in large clumps at her chest, ears, hips, the back of her head, and on her bottom. She also has two patches of dark fur on her back.
As Teppei suffered from the effects of overusing his powers, Yuki approached him. Thinking she was another enemy, Teppei prepared to fight her, but was shocked as she blew a cold burst of air on him instead, lowering his temperature and preventing him from burning himself up. Having done this, Yuki greeted Teppei with a cheerful good evening. The next morning, she was nowhere to be seen, prompting Teppei to believe she had been nothing but the result of a fever dream.
Yuki later appears before an upset Teppei and questions him about him fighting for humanity's sake, and tells him that nothing good will come from it. She then questions him about being a hero and protecting people and how they gave him attitude after he saves their lives. Teppei tells her to shut up and that his powers exist to protect people. He says that he hasn't lost his friends and asks who she is. She smiles, reveals her name, and says that she wants to be his friend.
She then listens as Teppei tells her his story up to this point, and tells him that as long as he is kind and just, with a good heart, she doesn't think he'll become a monster. When he questions this, citing Kirio Karasuba and Numazawa as evidence, she replies by saying that humanity isn't just about kindness and order, but also is made up of hatred and cruelty, which she believes translates into strength much better than the former. Teppei is surprised by her intuition, and asks her if she knows anything about the current situation, to which she smiles and replies in the negative, saying that this is just what she has ascertained by watching the town over the last month.
Yuki then warns Teppei that as Goblins recover from wounds abnormally fast, Numazawa will soon return for his revenge. She then expresses her concern that he will not be able to win, as this time around, the Acid Ruler will be at full power. Teppei affirms his decision to fight the man regardless, stating that he will die if necessary, which prompts Yuki to explain that the power of flames if not his only strength. After Teppei makes a sample piece from his molten iron, Yuki states that she figured he could do this, as he is capable of handling the substance in the first place. When the boy expresses his desire to make a sword with his newfound metalworking powers, the girl tells him that he can't without the proper equipment, telling him that he needs to make something simple for stabbing or hitting. She goes on to say that the most important thing he will need is not a means of attack.
Three days later, Yuki watches as Numazawa launches a surprise attack on Teppei, going over in her head the strategy the two of them had formulated, centering around the use of Teppei's Scale Shield. She then expresses her belief in the boy, saying that he will win through his strength as a human being. When Numazawa releases a wave of acid from his mouth, Yuki is shocked at this display of power.
Seeing that his friend Kazuki is in trouble, Teppei prepares to go to his rescue, only for Yuki to stop him, exclaiming that it is all a trap by Numazawa. When he demands to know if she means for him to abandon his friend, Yuki explains that sometimes heroes have to compromise in order to save as many people as they can. When Teppei argues that this is something he cannot do, she exclaims that it will be meaningless if he ends up dying, stating that it is a miracle that out of all the monsters out there, he kept his morals, and that he might be the only hero left to humanity. She is silent as Teppei states that she is a hero as well, and how her support has given him strength. As he prepares to leave, Yuki ruefully smiles at his hasty declarations, stating that she understands. Shen then transforms into her full Goblin form, shocking Teppei, and jumps into his arms, expressing her determination to protect him from both his enemies and himself.
When Numazawa attempts to land another surprise attack on Teppei, Yuki intervenes, landing several hits with sharp claws from her feet. Using the Acid Ruler as a springboard, she jumps onto the nearest building, shaking the blood off of her claws. Teppei uses her distraction to grab Kazuki, but is halted from fleeing as Numazawa attacks him once more, prompting Yuki to land another strike on the Acid Ruler's eye, buying the Iron Goblin enough time to safely deliver the boy back to the townspeople. Anchoring herself to the side of a building, Yuki wipes the sweat from her brow, and then dodges another attack from Numazawa. She expresses her worry over the gas finally getting to her, and then reacts in pain as some of the acid that her adversary had launched at her hits her foot, causing her to lose her footing. Before she is able to hit the ground, however, Teppei catches her, leaving her relieved and thankful. As the boy prepares to end his battle with the Acid Ruler, Yuki reminds him of their first meeting, telling him that she will save him if the same thing happens this time, and orders him to finish Numazawa off with 120 percent power. After he accomplishes this, Yuki smiles as the townspeople and Kazuki pour water over the victorious Teppei.
Later, after Teppei awakens, Yuki wishes him a good morning, telling him that everybody is ready to go. She then eats a quick breakfast, before transforming into her Goblin form. She then listens for any Goblins nearby, noting that there aren't many around at the moment, and gives Teppei and the townspeoples' van the green light. As they begin to set off, she notes that three Goblins have noticed them and are heading their way. After Teppei defeats them, Yuki senses something is off, noting that the Goblins' movements are irregular. She tells Teppei that she is going to investigate and warns him to be careful while she is gone. She then further reflects on the strangeness of the monsters' actions, thinking that it is almost as if someone is directing their actions. She wonders aloud if this many had retained their reason, only to be shocked by an unknown source.
She then lands behind Teppei, informing him that somebody is covering for them by sniping at the enemy, and that they should take this opportunity to withdraw. She arrives with the rest of the group at Yamatoyama City's subway system, and listens as the leader of the National Defense Force, Sakurayama Kenji, explains how the base fell to the Goblins, and why they cannot simply rescue all the people still trapped within it. When Kikuta, another member of the National Defense Force, vouches to go with Teppei and reclaim the base, Yuki informs the boy that he is probably the person who sniped the Goblins from earlier. After Kenji and Kikuta come to an agreement on recapturing the base, Yuki is seen in her full Goblin form, standing among a group of the defense force with equipment strapped to her body. Having been tasked with finding the Three-Eyed Goblin's real body, she cheerfully bids Teppei farewell.
- Transformation Control: Yuki has shown to have complete control over her transformation. When she transforms, she shakes a little and she grows while gaining her goblin features.
- Freeze Breath: She has the power to breath out ice-cold bursts of air, which were sufficiently cold enough to halt the disastrous side effects of Teppei's fire powers.
- Retractable Claws: She is able to freely unsheathe and retract deadly claws from her feet at any time she wishes.
- Enhanced Hearing: Yuki's hearing increases in her goblin form, as she was able to hear when goblins had noticed them and that they were coming.
- Enhanced Reflexes: Yuki has been shown to have incredible reflexes. Even when caught off guard by Kikuta's unexpected assault, she was able to avoid any injuries to her vitals, taking the otherwise fatal shot in her shoulder instead.
- Teppei Ushizume: Yuki understands that Teppei chooses to use his power to protect people. She then explains to him that, because he's able to melt metal at will, he'll be able to create weapons and shields. Thus, creating a spear and the Scale Shield.
- (To Teppei Ushizume) "...Where are you heading? What do you want to do? What are you fighting for? Why are you so used to this? I want to know more about you."
- (To Teppei Ushizume) "...You've sure lost a lot, huh? Friends, goals, hopes...so, why not stop fighting for humanity's sake? There's no point, and nothing good will come out of it. In the end, even all the fighting you've done this far was meaningless, right? Wouldn't it be better to give up on acting like a hero and just live doing whatever you want? Just like your former friend said before, that might be your true self. Those people are sure awful, huh. You risked your life and saved them, and yet they gave you that attitude without even a word of thanks. How about really cutting loose with that power of yours? There's no need to hold back! I mean, your power exists to burn cities to the ground, right?"
- (To Teppei Ushizume about becoming a monster) "I'm sure that as long as you're...how to put it...kind and just, and have a strong heart, you'll be able to stay human, even if you become a monster. It's all about not being a demon on the inside!"
- (To Teppei Ushizume on human nature) "You're probably right about a strong nature being the key to keeping one's personality, but humanity isn't just about kindness and order. There's also desire, hatred, and cruelty. Those elements are also factors in the makeup of people's souls. And factors like those translate into power much more readily. That's why the wicked became strong. I think that the so-called ogres and demons you've seen are human, except in appearance."
- (To Teppei Ushizume during his fight with Numazawa) "You will win, Teppei-kun...through your strength as a human being."
- "Yuki" (雪) can be translated as "snow".