Blast/Relationships

Saitama
Blast first met Saitama when the latter was with Flashy Flash and Manako in the underground of Z-City. At first, he did not see anything impressive from Saitama, only considering him to be a regular hero. However, in the Ominous Future, Blast became aware of Saitama's incredible strength during his confrontation with Garou, who has become influenced by "God". Later, due to Saitama traveling to the past and defeating the Hero Hunter in order to prevent the Ominous Future from occurring again, it is likely that Blast is currently unaware of what happened in the Ominous Future and therefore has forgotten about Saitama's encounter with Garou.

Tatsumaki
Due to Blast saving Tatsumaki when she was younger, Tatsumaki highly respects Blast. Blast would console Tatsumaki after saving her, telling her that she still has a sister that needs her protection and to ultimately not expect someone to come save her when the time comes. Tatsumaki would unintentionally heed this advice a bit far, distancing herself from everyone but her sister Fubuki. The memory of Blast saving her and his advice for her would provide her with the will to continue fighting Psykos and Orochi despite momentarily fainting due to injuries. The two would later join the Hero Association (not together) and are the two highest-ranked heroes in the association.

She is also capable of recognizing Blast, as when the entity "God" used a perfect illusionary form to get her to work with it, she realized the words "God" said didn't match Blast's and simply asked who it really was before seemingly falling asleep. Blast would later appear and showcase pride in her for resisting its temptations.

Due to her past troubles, Tatsumaki has come to put excessive expectation on Blast due to him saving her. Desiring his respect if she became strong enough, and more advice on how to live her life, secretly acknowledging her current state isn't her ideal or pleasent.

King
Blast was aware of King´s position and fame amongst the S class heroes, to the point of entrusting to him to look after the safety of Tatsumaki who was unconscious and badly injured.

God
For 20 years Blast and his collaborators searched for Mysterious Cubes that allowed people to come in direct contact with "God" in an attempt to analyze them, however 2 years before the present during his fight against Elder Centipete, Blast came in direct contact with the entity, upon refusing the tranfusion of power both of them engaged into combat where Blast ended badly injured in the aftermath. Convinced that keeping the existence of "God" away from the public and the Hero Association would be for the better, he isolated himself making it seem like he "vanished", and since then Blast and his team have been trying to keep God in check, on an attempt to keep him away from their dimension.

Empty Void
Blast and Empty Void were partners searching for Mysterious Cubes with other collaborators until one day "God" turned Empty Void into a Mysterious Being. 15 years ago, Blast fought and won his battle against Empty Void, who managed to escape from his grasp due to Blast's unwillingness to kill his former partner for good. Despite everything, Blast still seems to consider him his partner and has been looking for a way to turn him into a human again.