Fat Gum's Quirk is far more dangerous than My Hero Academia fans think

Fat Gum, aka Taishiro Toyomitsu, is one of the many characters in My Hero Academia that often gets overlooked due to his goofy design and lack of involvement in the narrative. The BMI Hero is usually seen by fans as a loveable tank - a Hero who takes the brunt of his enemy's attacks so others don't have to.

For those unaware, Taishiro's Quirk, Fat Absorption, basically allows him to absorb any object or attack he makes contact with into his body fat. This absorbed energy and force can then be redirected and released as a powerful counterattack. However, few people realized just how terrifyingly overpowered this ability is - until a recent discussion on Reddit brought it to light.

Disclaimer: This article is a speculative theory and reflects the writer's opinion.

My Hero Academia: The true nature of Fat Gum's Quirk, explained

Expand Tweet

Taishiro Toyomitsu, aka the BMI Hero: Fat Gum's Quirk, Fat Absorption, is described as the ability to absorb kinetic energy from attacks into his body fat and then unleash that built-up energy in a powerful counterattack.

His Quirk requires him to have a large amount of fat reserves, which he burns through whenever he uses his Quirk to absorb or redirect attacks. But if Fat Gum's Quirk actually worked like he claimed, then why does he get skinner every time he uses it?

For clarity, fat is primarily a storage form of energy in the body. Realistically, by absorbing energy through physical attacks, Fat Gum should be gaining more mass, or at least, maintaining it.

And after his Quirk is used up, where does the fat even go? It obviously can't just vanish in thin air. Then again, it's possible that his fat isn't getting compressed at all - if anything, it's probably getting metabolized.

Fat Gum as seen in My Hero Academia (image via Studio Bones)

A more plausible explanation of Fat Gum's power might be that he's burning through his fat reserves to generate kinetic energy.

In other words, Fat Gum's real power might be converting stored chemical energy (fat) directly into raw physical force. That would explain why he loses all his fat in an instant after a big attack. His fat wasn't just storing punches, it was actually fuel.

One Reddit user named u/Nordic_Krune recently made a post on the platform, where they discussed this idea and ran with it. The user and their roommate assumed a 200 kg fat reserve for Fat Gum, and figured that he could burn all of that with 70% efficiency, then deliver a punch in about 1/600th of a second - which is a realistic reaction time for trained fighters.

Additionally, the area of the punch was estimated to be around 10x20 cm. The resulting force of Fat Gum's punch was calculated to output more than 25 trillion Newtons - and that's equivalent to the force output of about 7000 tank shells. Or roughly 2.5 million 9mm bullets. It's also about 1/1000th the energy yield of a small nuclear bomb.

So, Fat Gum isn't just a human shield. He's got potential city-leveling energy in his fists if he ever went all out in a fight. Based on this, we can conclude that at the end of the day, Kendo Rappa and Hekiji Tengai got lucky in My Hero Academia's Shie Hassaikai arc.

Expand Tweet

After all, had Tengai not activated a barrier with maximum defense in time, both of them wouldn't just have been knocked out. They might have actually been reduced to ashes by Fat Gum's final attack.

Furthermore, the Reddit user and their roommate calculated the heat transfer from Fat Gum's energy release. If even 0.1% of that energy was converted into thermal energy in a 30 cubic meters room, the room would heat up approximately by 3°C, which is quite a lot.

Taking all the above points into consideration, there arises a question - why isn't Fat Gum a bigger threat in My Hero Academia? The simplest explanation is that he doesn't really need to be. Taishiro isn't a killer - he's a licensed professional Hero. He works in law enforcement; he doesn't need to go all out in every fight he's in. All he mostly does, after all, is restrain criminals.

Also, burning through his fat reserves leaves him in a weakened state. Unless he has instant access to food in the middle of a fight, his power is meant for a one-time use - meaning he can only go all out once per fight, if deemed necessary in the first place.

Final Thoughts

Fat Gum's Quirk is by far the best example of My Hero Academia's power system blending biological mechanics with anime logic. His monumental fight against Rappa and Tengai showed us that he's more than just a comic relief, and can get just as destructive as heavy hitters like All Might if he needs to.