Chizome Akaguro/Relationships

Tenya Ida
Stain despises Tenya for his desire for revenge against him. He scolded the young hero for prioritizing his selfish desires to avenge his older brother over saving the Pro Hero he was about to kill. Even after Tenya learned from his mistakes, Stain stopped at nothing to kill him, claiming that people do not change their views easily.

Tenya, though he hates him immensely for paralyzing his brother, acknowledges Stain was right about him and resolved to start over as a Hero.

During the Final War against the villains, Stain notes that Tenya and Shoto are "acting for the sake of others" hinting that his opinion of Tenya has begun to change.

Izuku Midoriya
Stain, like All Might, respects Izuku for his convictions and bravery he displayed in his fight with him. He acknowledges Izuku as a true hero for protecting others in spite of the danger. Because of his respect, he both spared Izuku when he first fought him and risked his life to save the young hero-in-training from a Nomu.

Izuku seems to also share a similar respect for Stain. When speaking with Tomura at the mall, Izuku confessed that while he didn't accept Stain's methods, he did at the very least understand Stain's desire and the ideals Stain stood for. Izuku also seems to be grateful towards Stain for saving his life from the Nomu.

Because of their encounter, Spinner prevented his comrade Magne from killing Izuku declaring that he was the person that Stain saw fit to save thus being a man worthy of the title of a true hero.

Shoto Todoroki
As with Izuku, Stain seems to also respect Shoto for his skills and convictions as a true hero, although this does not prevent him from attacking him with the intention of seriously injuring him, and criticizing him for relying too much on his Quirk.

Shoto, on the other hand, despises Stain for his ideologies about "fake" Pro Heroes, considering him nothing more than an anachronistic and murderous fundamentalist, and defending Tenya from his insulting criticism and his attacks.

Tomura Shigaraki
At first, Tomura wanted to recruit Stain for the League of Villains, but after explaining his motives and objectives, Stain views Tomura as an immature child who wants to cause needless bloodshed all for nothing. He did not hesitate to pin him down when they conversed and refused to join his alliance, which earned him Tomura's hatred. However, he was amused by Tomura's desire to kill All Might and destroy those who worship that caused him to see the latter had potential to grow.

Tomura also despised how Stain's capture was the main news story instead of the Nomu attack. After having a conversation with Izuku, Tomura discovers his true hate for Stain comes from his connection with All Might. Wishing to create a world without All Might, Tomura develops his own conviction and states he will use Stain's ideology as a stepping stone for himself.

Kuin Hachisuka
When he was Stendhal, he formed a partnership with Kuin, in which both benefited from each other, although that was not to mean they were really allies, as Chizome warned Kuin she will be judged by "Stendhal" sooner rather than later.

She helped Stendhal with the extermination of the Abegawa Tenchu Kai, and in return, she demanded him to return the favor by taking out specific targets for her. He obliged to Kuin's demand since even the lowest of filth has its worth.

After being defeated by Knuckleduster and being enlightened by his words, Chizome understood that what he lacked was resolve. Kuin Hachisuka makes fun of him about his need for resolve, for which he throws a knife that sticks into her eye hidden by the patch. Giving her for dead, he walked away without realizing that Kuin blocked his attack. Despite this, Kuin decided not to retaliate, considering since he will make things all the more interesting.

All For One
Chizome first saw the Demon lord, when he arrived at Tartarus after his defeat by All Might. He gave him a neutral glare, as he was escorted through the hall.

During All For One's mass breakout, Chizome took the opportunity to escape rather than join most of the prisoners in rallying with All For One.

In the Final War, Chizome and All For One personally meet when Chizome used his Quirk to immobilize the villain, as he prepared to finish a battered All Might. However, All For One broke free of the trap and expelled his blood to prevent himself from being caught off guard and overpowering Chizome. He revealed he figured he was up to something, when he didn't join him at the breakout. Before moving to finish him, All For One noted he owed the vigilante for contributing to the growth of the League of Villains and Tomura's development, though he announced his role was finished and he intended to steal Chizome's quirk. Defiant to the end, Chizome used his hands to mimic All Might's smile, before he was ultimately slain.

All Might
Chizome has a tremendous deal of respect for All Might and even states that he is the only true hero in the world.

His respect regarding All Might emanated from the respect he had towards him when he was a teen, since All Might was the reason Chizome initially decided to become a hero. Chizome's respect and admiration for All Might runs so deep that before finally falling unconscious, Chizome declared that only All Might is allowed to defeat him.

Following the Paranormal Liberation War, Stain finally meets All Might face-to-face in Kamino, but he calls him a “fake” desecrating All Might's sacred grounds. Even when All Might showed his muscle form, Stain refused to believe he was actually talking to him, calling All Might a man who helped people regardless of the power he held, showing that his respect for him runs deeper than expected. However, he did imply to All Might that he was already aware of his current state and everything he said was a means to motivate and inspire him. He further told him that if he is a true hero, to make use of his information from Tartarus, throwing a knife containing the data disk, as well as a personalized letter to All Might attached, toward him.

During the Final War, Stain saved All Might in his fight against All For One.

It is proven that he was well aware that All Might's new appearance and intervened on his behalf, as he needed to live. Stain put up a valiant effort and fell but ultimately his actions led to All Might regaining motivation.

Endeavor
Although it does not seem that they have met previously, Stain has a huge hatred and holds contempt towards Endeavor, considering him the epitome of everything that a hero should not be. When they meet, Stain enrages and challenges Endeavor and other "Fake Heroes" to try and defeat him in battle, releasing a malicious aura that paralyzes everyone with fear, even making Endeavor step back.

Koichi Haimawari
While he was still Stendhal, at first he respected the young Koichi for his dedication to being a vigilante. He once saved Koichi's life from an Instant Villain. When the villain runs away, Koichi thanks him for saving him and asks him his name. Before leaving, Chizome reveals to Koichi that he is called Stendhal and is a fellow vigilante. This meeting made a great impression on Koichi, who starts gushing over Stendhal.

But this changed when Chizome tried to kill Soga. At first, Stendhal warns Koichi not to get in his way as there is no value in saving Soga since all he deserves is a dog's death. But Koichi tries to save Soga and run away with him on his back. Stendhal praises Koichi's innate act of goodness but still considers him evil since those who side with evil have evil within themselves, and tries to kill him too until Knuckleduster arrives to save them.

Knuckleduster
Apparently, Chizome respected the "Vigilante of Naruhata", not wanting to fight against him when he arrived just in time to save Koichi Haimawari and Soga Kugisaki. Stendhal saw him as someone who is forging the path of righteousness in this crooked society and as a result, they shared similar ambitions. However, Knuckleduster disagreed totally with his opinion, viewing himself as completely different from Stendhal: he is a champion of justice while Stendhal is just an insane street murderer.

Disappointed by the fact they cannot reach a mutual understanding, Stendhal attacked Knuckleduster but got knocked out by him. Stendhal's nose was completely smashed in and he was forced to retreat, causing minor injuries on the Vigilante. However, his defeat was not a complete loss, as he became enlightened after hearing Knuckleduster's comments about resolve. Stendhal thanks him for this revelation before he retreats.