THE OVERHAUL QUIRK.
in essence, it’s destruction and restoration, but it’s not that simple. it would be easy to say “overhaul just changes the cells”, however, it doesn’t quirk work like that. it’s stored in the hands (and the feet, though this is unknown to kai), and can work if any part of his hand comes into contact with an object. note: this headcanon is directly tied to @necrotises, as this overhaul is the origin of their decay.
more under the cut. btw, this can be reblogged and be used for reference by rp partners only.
disassembly: the quirk itself has the ability to manipulate potential energy stored within an object, living or not, transforming it into heat or a kinetic energy at a rapid pace. in the case of overhaul, this transformation happens so rapidly that it must be pushed out with great force, resembling an explosion.
reassembly: it’s a bit more complicated than “overhaul puts the disassembled material back together”. rather, the quirk can pull back affected material, living or not, and reform it into kai’s image.
limitations.
precision: overhaul is not specific enough to splice down to atoms. he can get somewhat specific, but not specific enough to completely change the atomic makeup of an object. the object will always have qualities of its original form. that said, chisaki will do your transgender operations! (its reparations for accidentally misgendering magne. sorry mag. his bad.) he did his own top surgery, and opted to leave almost fishbone looking scars.
timeframe: reassembly can only occur for up to 15 minutes after disassembly. otherwise the ability to pull back the affected material is altered. were he to try reassemble after that time period, the object would need to be disassembled and reassembled once more.
two-halves: disassembly is possible without reassembly, but not the reverse. if chisaki is not intending to reassemble, the energy must be released. as we see in magne, compress, and that one hassaikai babysitter, we see the “explosion” mentioned earlier. blood is splattered everywhere, and a mess is made. this is inevitable. were he to do this to another object, it would react similarly.
specifics.
restoration: kai can decide how much of a person is reassembled, but this takes concentration to adjust to an imperfect level. the quirk naturally seeks to reassemble to a near-perfect level. it’s likely that if an ally is ressembled, they will find all cavities and minor injuries completely healed. this may also happen if he’s in a rush, or looking to display his power.
fusions: quick note here, kai can use overhaul through someone else’s hands, but only if they are fused to his body. there’s no magic possessing or anything. he must have the hands fused to his body in order for it to work. back to the main point. kai can fuse any two objects together, including himself, though it is not necessary.
fusing himself: kai will always remain the dominant consciousness if he’s fusing with another human. the other will be in a dream-like state, and likely will have blurry memories of the events once split. additionally, he can use the quirks of others once fused, as we see with nemoto.
fusing others: whichever will be the dominant consciousness is a gamble. he can’t decide that; it’ll be something of a battle between the minds being fused. and because of that, fusing two humans is a risk. chisaki can fuse more than two beings together, but the consciousness situation becomes more tricky after that, so he prefers to only fuse two, or fuse with himself.
stability: overhaul is an unstable quirk. anything may accidentally be overhauled when the gloves are off. should chisaki experience heightened emotional stress or external stimuli, he has little control over what gets overhauled. he has no issues immediately overhauling whatever puts him under such intense stress, so be mindful of staying in his good graces. additionally, many pillows and bedsheets have been overhauled during times of intimacy and ecstasy. the quirk itself was more unstable when he was younger, which the gloves helped. on top of this, he trained to keep himself calm in most situations, but it’s still a gamble when the gloves metaphorically (and physically) come off.
experience.
disassembling: being disassembled, though it seems like the most painful part, is actually the calm before the storm. it’s quick, and not the worst pain anyone is likely to feel. its uncomfortable, of course, as any manipulation of energy in the body would be. there is a warmth as the body part “explodes”, but as mentioned above, it’s so incredibly quick. the victim might not even know they were disassembled.
reassembling: this is where all the pain that should've been experienced in the disassembling stage catches up to the victim. as nerves are rebuilt, the pain from the disassembling is finally felt, leaving the victim in genuine agony, even for those with high pain tolerances.
those being reassembled can expect to experience:
mind-altering pain. the inability to speak or stand. they may also experience temporary amnesia.
extreme psychological distress. possible delusions/hallucinations from the pain.
physical symptoms. nausea, vomiting, heart palpitations, sweating, muscle spasms, and more.
chronic symptoms will include:
common ptsd symptoms. depression, anxiety, paranoia, nightmares, flashbacks.
phantom pains, despite the body being restored.
upgrades.
atom-splicing: were overhaul to upgrade this quirk, he would likely be able to splice things down to the atom . this would allow him to split quirks from owners, change the entire makeup of something, and so on.
contact: another potential upgrade would be the ability to overhaul something from not just his hands nor feet. rather, his arm or leg could brush against something and change it.
overhaul and chisaki.
the quirk takes little from him. while some quirks come at the cost of stamina or concentration, overhaul doesn’t ask much from kai. he doesn’t need to know the makeup of something to restore it, nor does it take time for him to overhaul an object or person. the process happens in seconds. he attends medical school in order to get a better understanding of anatomy for his ultimate goal, though this knowledge helps him adjust the level of reassembly.
it has little psychological effect on him, and the only thing he “feels” when overhauling is moderate heat in his hands from the energy transfer. he does experience the same pain as a victim would when he overhauls himself. he trained to handle the pain and work through it quickly, but he still remarks it as unpleasant.
conclusion.
overhaul is an incredibly powerful quirk that certainly should’ve earned more than a “b-rank” in ultra analysis. it’s ultimately unstable, though chisaki has trained for the amount of control he has currently. it has many different applications, though the symptoms and side effects of being overhauled are intense.














