Reason: Depictions of hell and the underworld. Depictions of torture.
The Flopsworn is an army of anomalous demons in a dimension known as the Flop led by a demonic being known as the Flopper. When a soul is sent down into hell for committing terrible crimes (which include hating Bingus) they are sent to the realm of the Flopsworn. Where the now doom soul spends eons being eternally tormented by Flopsworn in a twisted game where no one wins. Eventually, the tormented soul becomes the tormentor and becomes a Flopsworn after a thousand decades of suffering. Some beings join the Flopsworn willing, multiple members of the Cult of Foo in fact became Flopsworn after summoning a damned soul into the mortal plan where the group tormented the soul. The Flopper grabbed these horrible Floppas and sent them to torment and torture for the rest of existence.
The Flopsworn feed on the misery and suffering of souls as it grows their power. Without these emotions a Flopsworn will wither into ash and fade, the remains of their twisted souls being sent to oblivion. The Flopsworn are an army of the trillions and ravage and ransack whatever realm that dares open up to them. Thankfully, a veil separates their realm from ours but many seek to break such a barrier to bring about the end times. The Flopsworn are behind some major events in history, including sending Bingus the visions of The Destroyer and convincing him to commit suicide, where he would become a tormentor of souls. The Flopsworn are actively fighting a uphill battle against the F.C.P Foundation.
It is theorized that The Flopper, the leader of the Flopsworn and their twisted realm is actually the remnants of The Destroyer. However this does not matter, The Flopper sees that after the death of any being its soul is sent to a heaven like plane of reality. Even the sinful live a luxurious eternity after their demise. The Flopper must stop this, and he sets off to do so. The Flopper creates a realm of suffering out of Soulplaque and steals sinful souls from the heavenly realm above. He mercilessly torments them into they are a mere shade of their former glory, soon he has a small army. Once this army is finally created things begin to automate. Flopsworn steal sinful souls from their fate of goodness and send them to Flopghast to be forever tormented until they join the legion. The Flopsworn have craved more power however, and seek to tear a rift into the mortal plane to access it and meld it with their realm of torment. The Flopsworn attempt to do this with brute force, with a single Flopsworn escaping. This Flopsworn eventually grew so old that it began to evolve into a being known as the Trollge. The F.C.P eventually found this futile rift and sealed it, and learned of the Flopsworn from a vision. The Flopsworn were added as an F.C.P as a threat to the Floppaverse by the foundation. The Flopsworn began brutally attacking the F.C.P via Trollge and war was declared. Currently the Flopsworn still wage an eternal conflict against the F.C.P Foundation.
The Floppa Clan Incident
In search for more power to rule the world, Floppa Clan attempted to open a portal to another dimension filled with energies that would empower Big Floppa II. Unfortunately, they opened a portal to the Flop instead. At first, multiple weak Flopsworn easily overpowered Big Floppa II until reinforcements arrived. With the help of multiple vehicles of war the Flopsworn were repelled and the portal sealed. Big Floppa II, realizing that he was not nearly has powerful has a though, Big Floppa II went into hiding for a few months. Only to return and make a speech about power.
Sogga was once a kind rapper, but the Flopsworn have a way of ruining good things. When Sogga's soul left his body he was pulled down into the Flop and was tormented by horrible beasts of bingus, metal, and flesh until finally he became their masters. Now known as The Creaturemaster, Sogga hones his craft and creates the most horrifying beings in existence, ready to slaughter and torment.
Bingus was destined to join the Flopsworn, from the whispers to the suicide. When Bingus did die he was sucked straight down into the domain of the Flopper. In life Bingus was a dictator, and after years of torment he would be one in death as well. Bingus commands the eternal armies of the Flopsworn along with his brethren. Nothing is left of Bingus, only a husk of anger and resentment that he is called a "ballsack" remains, but alas soon he will get his revenge, soon his armies will breach the Floppaverse, soon or at least he thinks that.
Supreme Deathlord Flopius
Supreme Deathlord Flopius, or just Flopius is a highly powerful Flopsworn torturer and commander. He commands most of the Flopsworn armies, even Bingus quivers at the sight of Flopius. Flopius is known to punish failures in his army by forces their flesh to meld to the walls of the Flop, causing many locations in the Flop to be made out of flesh. Flopius is skilled in creation of life and has created most types of Flopsworn. Flopius is known to be cunning and patient, unlike Bingus in battle.
Gargantious Sloopa, famed slayer of Bongus and Wrinkus was to be routinely punished by the Flopsworn for murder. However, they severely underestimated his willpower. He managed to kill his tormentor, Miserycrafter Floperbing and steal his barb wire whip and mossberg-500 shotgun. Sloopa fought honorably against thousands of Flopsworn before he finally was noticed by the Flopper himself and instantly transported into his chambers. This is where the Flopper impaled Sloopa in the thigh and transported him back to a more capable tormentor. It took only 5 weeks to tranform Sloopa into a Flopsworn because hes a weak-ass bitch. Ironically he works besides Bongus in death, one last ironic torment.
Bongus was killed by Sloopa and was not nearly has hard to transform into a Flopsworn as Sloopa. He was easily converted when he was forced to watch his son being slaughtered in an entire library of ways. Bongus was bound to a massive hulking suit of armor, transforming him into little more then a beast. His tormentor, in some sort of wicked ironic game forced him to cooperate with his killer and enemy, Sloopa.
Hunter Bingus was assassinated by an unknown member of the Floppa Clan during a meeting in the John F. Floppedy conference room. He was very hard to process into a Flopsworn, because he had nerves of steel. Eventually, he gave in, and he was bound to a massive hulking suit of armor, and became no more than the rest of them. From that day on, he was known as The Underworld's President.