S Gene
The s gene
Experiment Type: Bio-Genetic Trait that enhances human performance and grants superpowers
Side-effects: Mental Instability
Users: Shiningman
Shuto Katsuragi

The S Gene is something that is referred to as the Legacy of Shiningman. So far there is little information as to what it is about or why it exists.


Not much has been revealed about this mysterious genetic trait, though its roots go back more than seven years to the orginal S Project, or Project Shiningman. What is known about it is the fact that it was the source of Shiningman's powers, though apparently it was considered to be very dangerous and should not have been passed on to anyone. It may be the reason why the project ultimately failed and directly or indirectly caused the deaths of its creators, Tongo Mizushima and his wife. Shiningman himself would also disappear from public view, but not before the S Gene was passed on to two recipients. These people were confirmed to be Shuto Katsuragi, and the one who would later become the hero IS-KA .

Mention of the S Gene would resurface seven years later as the Hero Association becomes a well-established provider and regulator of low-level superpowers, while the Jackal Organization was formed to oppose it. Tongo Mizushima's eldest daughter Crea and his father Gengo would expand on Tongo's work by creating the Ratman Suit and the Append Gear, which were only compatible with a user with the S Gene. Therefore, Crea began searching for the person whom Shiningman had saved and could have transferred the S Gene to, which in this case was Shuto.

With the appearance of Ratman and his first operations against the Hero Association, Shourichirou Kizaki began to take interest in him and the possibility of Ratman having the S Gene. Through Kreios, it was later confirmed that this was indeed the case. Furthermore, others with interest in re-creating or obtaining the S Gene began to appear. Dr. Teramishi, one of the scientists who worked on the S Project, was attempting to achieve within his ward Shiki Kazamori; the same same power that Shiningman possessed. His plans eventually fell through and he was arrested, but the stigma of the S Gene would persist.

With the appearance of IS-KA and the Hero Booster Program, the S Gene would once again begin to influence the course of events as low-ranking heroes are seduced by its power, but pay the price as they are driven insane and begin attacking innocent people. Fortunately, this disaster was averted though the instigator of the riots, IS-KA, still remains at large.

Despite all of the negative characteristics of the S Gene, there are still those who covet its power and do not think of the consequences.

Traits of the S Gene

The exact properties of the S Gene are unknown, but it has been shown to greatly enhance the physical abilities of the human body, and grant the person a number of superpowers. Unlike the low-level powers and weapons provided by the Hero Association, the S Gene imparts superhuman abilities that far exceed that which is currently available.


Shuto in pain from the S-Gene side-effects

Interaction With Another S Gene:
Apparently, the S Gene will begin to react when it is in relative proximity with another individual who has the S Gene as well. If one is not used to it, the S Gene will cause the person to go into painful seizures. This is displayed when IS-KA visited Shuto's school, causing Ratman's alter-ego to collapse during gym period, though IS-KA was not physically affected. IS-KA makes the comment that the S Genes were resonating with each other. Furthermore, as a result of this interaction, Shuto was unable to act against IS-KA as Ratman. Now IS-KA is searching for him for some dark purpose.

Ratman Hits Hard, Mr. Big Horn Barely Feels It.

Superhuman Strength, Speed and Agility:
The person becomes physically stronger and faster. He/She is able to perform feats that would be physcially impossible by normal human standards. The D-Rank Duo became strong enough to stop a moving truck with their bare hands, while Mr. Big Horn gained enough power to go head-to-head with Ratman.

Takes a big hit, keeps on going!

Resistance to Pain:
Once affected by the S Gene's more potent and deadly effects, the subject begins to feel little to no pain at all, making him/her nearly unstoppable, regardless of how much damage is received. Despite taking Ankaiser's and Ratman's hardest punches, those who were affected were able to keep on attacking.

S Gene's Body-Morphing Effect

Body Morphing:
The S Gene is able to manipulate the molecular structure of the subject's body, thereby making the flesh malleable and able to reshape itself. Ratman is able to create the Mega-Rat Claw, while Rio went up against a D-Rank hero who shaped his arm into a blade.
Dark Energy:
IS-KA has demonstrated that the energy given off by the S Gene can be fired off like a projectile weapon, or transmitted through a Smartphone to others who had downloaded the Hero Booster Program. Shuto has also shown such an ability, but so far, it has only been displayed in small amounts when he is sinking in and out of his Animalistic State or reshaping his body. This trait was also seen in users of the Hero Booster Program. IS-KA has later shown to be able to manipulate this energy, either to create arms that can grasp an object from a distance, or to create a kind of 'black hole' that can engulf virtually anything that comes in contact with it.
Shining Ray Attack
Light Energy:
Considered as a direct opposite to the dark energy, a more pure form can be released, either in the form of Ratman's Breath Laser or his Shining Ray Do Oruta. This is also connected the Shiningman's Killer Move, the Shining Ray.
Berserk State:
This is possibly the deadliest trait of the S Gene as those who possess it or receive its power, will inevitably go insane or sink into an animalistic state. He/she will begin attacking anyone perceived as a threat, be it friend or foe alike, with deadly force. This is most likely the reason why the S Gene is considered as dangerous and should not have been passed on to others. Unfortunately, this is also the side-effect to the Hero Booster Program.


  • In Chapter 1, it is suggested by the Fake Hero that the Append Gear only works when "someone special" activates it, which could allude to Shuto possessing the S Gene.
    • Further added to this suggestion is the fact Crea shows regret that they had to force him to bear their responsibility and stating that it is because only Shuto is capable of doing so.
    • Gengo also agrees with this as he states that only Shuto can be Ratman.
    • Shuto was initally unaware of the S Gene's existence or even that he had it.