Since Spider-Man was introduced in Amazing Fantasy #15, his most persistent foe has been his high school nemesis Flash Thompson. Thankfully, Flash matured greatly over time – even befriending Peter Parker and serving as his best man in his wedding to Mary Jane Watson. Later stories had Flash join the military and lose his legs in battle, only to regain them (in a fashion) by becoming the symbiote superhero Agent Venom.

One aspect of Flash’s character that even long-time Spider-Man fans don’t know, however, is the story behind his name. While “Flash” was later revealed to be a nickname, few writers delved into its origins – until one popular Spider-Man animated series finally gave a hilarious explanation for the name – and an even more surprising revelation about just who gave Flash his name.

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Interestingly, Flash was one of the few members of Spider-Man’s supporting cast to even have a full name in Amazing Fantasy #15. Stan Lee and Steve Ditko initially intended the issue to be a one-shot story and didn’t put a lot of thought into creating a fully realized cast of characters (even recycling Aunt May and Uncle Ben from a previous story they did in Strange Tales). Once Spider-Man took off, however, many of the background characters suddenly increased in importance as later writers fleshed out their personalities and histories.

In Flash Thompson’s case, this led to him becoming an unexpectedly humorous character as he idolized Spider-Man – even starting Spider-Man fan clubs – but bullied Peter Parker. Flash regularly got into trouble in the early issues by dressing up as Spider-Man and getting captured by his enemies, requiring Peter Parker to reluctantly save his bully. Later stories, however, gave Flash a bit more depth and pathos. Flash later admitted he had an abusive father who drank too much, behavior that Flash later emulated when he also succumbed to alcoholism. Peter eventually developed some sympathy and even respect for Flash, and later came to regard him as one of his best friends.

Eventually, Flash also revealed his real name – Eugene Thompson. While neither Flash nor his friends used this name most of the time, the origin of his nickname “Flash” became a source of speculation for many fans. Some wondered if Flash had been named after the science fiction hero “Flash Gordon” or even the DC Comics speedster “The Flash.” Considering Flash was a high school football star and a popular kid, “Flash” could easily refer to either his speed or his “flashy” attitude.

However, in the Spectacular Spider-Man animated series episode “First Steps,” it turned out that neither of these theories were correct. In the episode, Peter revealed that when they were in nursery school, he and Flash were actually best friends. During this time, the young Flash apparently had a tendency to… run around with his pants off. The episode even shows his mother kept a picture of 4-year-old Flash frolicking around pants-free (with a strategically placed flower hiding his nether regions). “Who do you think gave Eugene his nickname?” Peter quips to his friends. “It wasn’t because he ran fast.”

It’s a hilarious explanation of how Flash acquired his nickname by basically “flashing” people in his younger years – and possibly another reason why he hated Peter Parker for giving him the name. Given that Marvel regularly retcons its stories, Flash may start giving out different origins for his nickname – but given how humiliated he was about the story behind his name in Spectacular Spider-Man, it’s still more than likely this is the true reason that Spider-Man’s biggest bully was named Flash Thompson.

Next: Could The MCU’s Flash Thompson Become Venom?