Fallen Ones (咎落ち, Togaochi) are former humans whose bodies and minds have been overtaken by their Innocence. Typically, the prognosis is terminal. 
The one fully transformed Fallen One shown so far, Suman Dark, took the form of a massive white floating torso with huge holes at both shoulders, as well as at the top of the neck and a single hole below the waist. Floating above the neck hole was a large halo, and at the location of the heart there was a porous material where Suman's main body was. Where the waist should have been there was a large number of pipe-like protrusions, forming a large flat area at the base of the torso, with a giant eye-like appendage taking up the bottom.
The area inside of the Fallen One's body, accessed at the porous area where the former Exorcist's human body is located, is a tumultuous sea of memories, with the Innocence of the former Exorcist located somewhere in the middle within a protective sphere.
The fallen ones formed from non-accomodator seem to be different as Lenalee didn't aknowledge that she was facing a Togashi before seeing Suman's main body. 
A Fallen One can be formed in one of two ways; either a person who is not an Accommodator attempts to force a synchronization with a shard of Innocence, or a proven Exorcists betrays the will of God/the Innocence, the synchronization rate between the Exorcist and their Innocence dropping below 0% and the Innocence turning on their Exorcist and draining their life force in order to resynchronize with a new Accommodator.
Once a person becomes a Fallen One, they typically die within a twenty-four hour time period, and during this time the Innocence forces their bodies to expel massive amounts of energy in order to strain their human bodies until they give out. After the Fallen One dies, the Innocence returns to normal and is ready to resynchronize with a new Accommodator.
Before becoming a full transformed fallen one, someone who attempts a synchronization despite not being an accomodator will suffer various deffects such as gauntness, and/or deafness. It appears that someone who is not transformed yet can still be saved if the experiments are stopped before the final synchronization. However once he becomes a fallen one, he will surely die. 
Even if the human body of a Fallen One is successfully severed from their Innocence before the human body dies, the human that is left over suffers complete brain death, likely the Innocence's final punishment in the event that it cannot kill the one who betrayed it.
Personality Traits Edit
Becoming a Fallen One amplifies whatever hatred the former human that is the base of the Fallen One's body bore for the Innocence and/or God that led to the Innocence overtaking their bodies, altering their personalities and making them focus on destroying everything around them. However, this does not necessarily mean that this is how the human, themselves, felt to any great magnitude, nor does it mean that this is how the human would continue to feel one (if) they are brought to their senses. This is exemplified by the case of Suman Dark, who became a Fallen One after be begged for his life from Tyki Mikk so he could see his daughter again, and then expressed genuine remorse when Allen Walker woke him from his bloodlust.
Fallen Ones 'attack' indiscriminately by pouring out large, concentrated beams of energy from the stubs that are their necks and arms, as well as the giant eye at the bottom of their forms. Even without a specific target, though, they would continue to expel the energy in order to kill their host, either doing this until their host dies or until an outside force destroys their body.
Known Fallen Ones Edit
- "Toga" means "blame" and refers to the "fault" of the person who attempted a synchronization without being blessed by God.