Saitama met Bang when the giant meteor was heading towards Z-City. Bang was amazed by Saitama's strength and tried numerous times to recruit him into his dojo, but Saitama always turns him down. Bang will occasionally invite him to cookouts and vice versa.
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 of recruitment has caused Genos to lash out at him on occasion.
Bang and Darkshine share mutual respect towards each other.
Bang respects Tatsumaki, but is often irritated by her immaturity and her violent tendencies.
Out of every hero in the Hero Association, Atomic Samurai only acknowledges and holds a deep respect for Bang. He once stated to Saitama that he only acknowledges the strong, which could be a reason for Atomic Samurai's respect to Bang, who is one rank above Atomic Samurai. His relationship with Bang is friendly, with a tad bit of rivalry between them, though this mild rivalry appears to be one-sided as Bang doesn't view Atomic Samurai as a rival. He also displayed concern for Bang when he was struck by Melzargard.
His former teacher Bang taught Garou everything he knows about fighting. After Garou went on a rampage and attacked his fellow students Bang kicked him out of his dojo. After he heard Garou started hero hunting Bang recruited his brother and went out to stop Garou.
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Garou does not respect Bang as a person, but he admires Bang's martial arts, even copying a combined technique of Bang and Bomb as his own. Despite the villainous acts he has committed, Bang ultimately still cares for Garou. Garou recognizes Bang's lingering affection for his former student from how different his punches were when he was expelled. It is unknown what Garou now thinks
Bomb is Bang's older brother.