Genos met Saitama after Saitama killed Mosquito Girl. Genos was about to self-destruct in an attempt to defeat the monster, he instead found himself shocked to discover that a normal looking person had killed the monster that almost killed him with one hit. After being saved, Genos asks to be Saitama's disciple, which Saitama nonchalantly accepts, thinking he wasn't serious. Though Saitama was annoyed by the thought of having a student, he gradually warmed up to Genos, even becoming angry after hearing he was defeated by the Sea King. Genos convinces Saitama to let him live in his apartment by offering to pay a substantial sum in rent. Genos does irritate Saitama at times with his intensity, lengthy explanations, and the pervasive misunderstandings between the two. Genos has a great deal of respect for his master. He is in complete awe at Saitama's phenomenal power and abilities, and has said before himself that he can't imagine reaching Saitama's level of power. He is firmly dedicated to stay as a disciple to Saitama, and strongly rejects anyone who tries to make him their disciple or lackey, feeling the need to protect his master's honor. He also discourages Saitama from taking on any new disciples.
He also knows when to let his master handle a situation.
He greatly values Saitama's humility and carefree attitude, as he respects Saitama's choice to not always report the monsters he kills. He only ever once lashed out at him, when Saitama explained the origin of his unlimited power was simple training, since Genos was curious to find out and still is. He also knows when to let his master handle a situation. For example, he didn't stop Saitama from giving the weaker heroes all credit for the defeat of the Deep Sea King, even though it could have strengthened the reputation of his master. Genos tries to do whatever he can for his master, and will express extreme dismay when he is unable to perform the tasks asked for by Saitama, no matter how insignificant or nominal they may be. Since Genos often tries to anticipate Saitama's desires, and Saitama's baldness seems to be a afternoon spot for him, a running gag in their relationship is that of Genos trying to "help" Saitama with his baldness, even setting up an appointment with Dr.
Saitama has been a strong influence on Genos, encouraging him to mature in his mentality.
Kuseno to get Saitama artificial hair implants. Despite his confidence and faith in Saitama's seemingly limitless strength, he cannot comprehend the true power Saitama wields. When Genos encounters Gouketsu, he thinks Saitama would need help to defeat such a powerful monster. However, unknown to him, Saitama came out victorious without a scratch on his body. Saitama has been a strong influence on Genos, encouraging him to mature in his mentality. Genos references Saitama often, especially before some of his most bold acts of heroism. Genos has had a strained relationship with Tatsumaki due to their conflicting personalities and interests. She only ever referred to him as "Demon Cyborg" and has smashed him through walls or sent him flying on multiple occasions. Their relationship is not helped by her rude treatment of Saitama, which infuriates Genos. Despite this, Genos assists Tatsumaki in her fight against Psykos and Orochi by deflecting attacks meant for her and providing covering fire. Through this he is able to earn newfound respect from her as he distracts the fusion long enough for Tatsumaki to rescue the rest of the heroes from the Monster Association Headquarters. She compliments Genos for his efforts, and they are both later seen cooperating with Drive Knight against the monster. After Fubuki saves Genos from overheating, he immediately returns to the battlefield to aid Tatsumaki.
He helps save her from Fuhrer Ugly and Gums, and even uses his own body to protect her from Black Sperm. When Black Sperm grabs her, he quickly rescues her and is struck into the ground for it. She expresses concern for him, but he assures her that he has had his body's armor upgraded to defend against such blows ever since she started knocking him into walls. While the two don't interact much Genos possesses a certain amount of respect towards Bofoi due to his powerful weapons and scientific genus. According to Drive Knight, Bofoi is Genos' enemy, causing Genos to become interested in Metal Knight. While the exact nature of their relationship is unknown, the two are shown to be friends. Like most characters, Genos is unaware of how weak King truly is. King seems to be somewhat worried about Genos's tendency to use Saitama as a reference to get stronger. The two get along fairly well. Bang passes advice onto Genos whenever he needs it and Genos holds a certain amount of respect towards Bang due to his martial arts skills and rank in the hero association. Like with Saitama, Bang tried to recruit Genos for his dojo but is turned down, and this constant attempt at recruitment has caused Genos to lash out at him on occasion. Like with Saitama, Bang often attempts to be a master or mentor for him, but Genos rarely listens to his advice. Genos still holds Fubuki in contempt as noted when he congratulated his mentor on nearing B-Class but voiced his misgivings about it's highest-ranked heroine.
39;s ongoing attempts to recruit both him and Saitama into the Fubuki Group.
He is aware that Fubuki practices 'rookie crushing' to maintain her spot at the first ranked class B hero. Genos's first impression of Fubuki, in person, is negative since she was aggravating Saitama, trying to convince him to join the Fubuki group. Seeing that Fubuki failed he looks down on her with smug satisfaction and continues to think little of her for some time after that. Despite being soundly rejected by Saitama and Genos, Fubuki is undeterred and Genos continues to reject Fubuki's ongoing attempts to recruit both him and Saitama into the Fubuki Group. Despite their tense relationship Genos does listen to Fubuki's discuss her relationship with Tatsumaki. He seems to resonate with her plight finding themselves in the shadow of someone with incredible power. He even asks her why she doesn't try to move up to A-Class, admitting that she has the skill to be an A-Class hero. However, Genos is still cold to Fubuki, and sees her as being a league below him. Her consistent attempts to insert herself into events irritate Genos, and come to a head when Fubuki attempts to recruit people sharing a hotpot together at Saitama's house. He directly threatens Fubuki, and when Dr.
Kuseno asks him to calm down, he asserts that 'that person' or 'this one' is not a friend. When Fubuki suggests waiting for Saitama before the Monster Association Invasion, Genos ignores her. However, Genos's opinion of Fubuki begins to change when she saves his life. After fusing with Drive Knight, he is about to overheat when he falls to the ground close to where Fubuki, Bang, and Bomb are standing. He insists that they get free of the immediate blast radius because 'even she' is too valuable to lose. Fubuki disregards Genos's command telling him to be quiet. She uses her psychic ability to heal his organic parts, and stop him from over-heating saying that 'even he' is too valuable to lose as well. Genos does not directly thank Fubuki but does give her his jacket, and seems to have a renewed respect for her as a hero. Genos treats Drive Knight with the professionalism and respect of a fellow hero and cyborg. When Drive Knight and Genos first meet all the information Genos knows about Drive Knight is from the Hero Association. Drive Knight warns Genos that Metal Knight is his enemy. It's unknown what Drive Knight knows about Genos but Drive Knight responds to Genos with immediate recognition. It appears Drive Knight has some knowledge of Genos beyond the Hero Association. Genos trusts Drive Knight enough to cooperate with him during the fight against Psykos and Orochi. Drive Knight and Genos fuse to combine their power.
However, once Genos is about to overheat and the barrier was gone Drive Knight abandons Genos dropping him and flies off. Genos is greatly indebted to Kuseno for saving his life and considers him a father figure. Kuseno in turn cares about Genos and helps him anyway he can. Genos discusses with him his opinion on Saitama in admiration, something Dr. Kuseno has noted on several occasions. Along with Saitama, he is the person Genos most loves and admires because of his intelligence and help, and has gone as far as standing up for Saitama because the latter called him "old man", though he later apologized for his attitude after Saitama told him to not take it so seriously. Dr. Kuseno is also happy for the impact Saitama has had on Genos, as it helped the cyborg recompose his emotions and suppress his thirst for vengeance. Like Saitama, Genos strikes an odd, even harsh, relationship with Charanko, mostly because he also refuses Bang's offer to join his dojo and learn martial arts. Genos is even more rude than his master in this regard, as he doesn't hesitate to chock Charanko and beat him when he disrespects Saitama and him too much. He doesn't show much respect towards his abilities either.
They seem to be on more polite terms than before, but they still haven't built a friendly relationship like Saitama has (in his own way) done. Due to Sonic's obsession with Saitama, Genos despises Speed-o'-Sound Sonic. He also considers Sonic a rival and a reason to become stronger. He offers Saitama to eliminate him for his master, but Saitama refuses to do so, saying Genos wasn't much better ability-wise (he actually wanted to avoid his house being destroyed). Genos does not respect Garou, seeing him as just another thug at first, and is later surprised by his strength. He comes to recognize Garou as a real threat, and is impressed by Bang's training of him. Genos was astounded by how much Garou had changed in the short time they last battled. As the conflict with the Monster Association was reaching its climax, he could barely recognize what the Hero Hunter had become. Genos absolutely loathes the Mad Cyborg, he claims it to be his arch nemesis. After having killed his family and destroyed his village at the age of fifteen, Genos has made it his personal mission to find and eradicate the Mad Cyborg and avenge his family. Though he's spent most of his time training with Saitama and has not had much chance to search for the cyborg, destroying it is still at the forefront of his mind; after having defeated Armored Gorilla, Genos asks him whether there are any other cyborgs like him that attacked a village, showing he's still determined in his mission.