Flashy Flash/Relationships

Metal Bat
They had limited interactions during the anime and OVA. However, neither of them could get along with one another. In both moments, Flash would instigate a verbal conflict whenever Metal Bat is talking. This usually ends with Flash mocking Metal Bat and Metal Bat's temper escalating the conflict between them.

Superalloy Darkshine
'''The following section contains Webcomic spoilers. You have been warned manga-only readers.'''

While there was never a true interaction between the two, Darkshine and Flash are known to be a dangerous combo in battle. The two stood together against Garou alongside Puri Puri Prisoner.

Saitama
'''The following section contains Webcomic spoilers. You have been warned manga-only readers.'''

Flash mistook Saitama as a monster and the two had a brief scuffle. After clearing the misunderstanding, the two became acquaintances with one another, with Flash acknowledging Saitama's superior abilities.

After being defeated by Garou, Flash was one of the few who regained consciousness and witnessed Saitama defeating Garou. In addition to acknowledging Saitama's strength, Flash decides that Saitama needs a teacher to polish his strength.

Tatsumaki
Flash and Tatsumaki have an unpleasant relationship with one another, just like with other S-class heroes. However, he appears to not be afraid of her and is willing to scold her back whenever she insults him. At one point, he insults her powers, saying they halted her physical and mental growth.

Gale Wind and Hellfire Flame
While their relationship is unknown the two ninjas plan to kill Flashy Flash.

Sweet Mask
Flash does not like Sweet Mask's authoritative and egotistical attitude. While he has some disdain towards some of the S-Class heroes, the tone he gives off is either of annoyance or even teasing, as seen with his interactions with Metal Bat. Flash's displeasure towards Sweet Mask goes to the point of eliciting his murderous intent towards the fellow hero. He goes out of his way to instigate a challenge against Sweet Mask.

Shadow Ring
The two share the same background of being grown and trained in the art of ninjutsu and employing themselves into the Hero Association. Shadow Ring is one of the few heroes Flash shows any respect towards. He complimented Shadow Ring's ninjutsu, even asking her for details to her technique. For Shadow Ring, she is very impressed with Flash's speed.

Speed-O-Sound Sonic
Sonic was Flash's classmate in the 44th class during his time as a trainee in his hometown. Their relationship so far is unknown but Flash responsible for making him the only survivor of the 44th graduation class.

During the conversation with Gale Wind and Hellfire Flame, Sonic shows no ill-feeling toward Flash.