Chapter Text
The first time it happened, Tokoyami had been 9 years old and his parents had been fighting in the other room. Dark Shadow had been staying between him and the door that led from his closet into his bedroom, their ghostly visage a rare source of comfort to the bird-headed child. The sound of his parents yelling at each other had been scary to him, and Tokoyami had felt something ever so softly click into place. He had moved his hand to hold the end of his beak, but it wasn't where he had known it was. He had moved his hand closer to his face until he had met the end of his beak, feeling a bit rounder and the slightest bit fuzzy like it had when his Quirk had first manifested four years ago.
"Fumi?" Dark Shadow had asked, turning to look at him in worry
When it had ended, they'd tried to figure out what exactly had happened. It had taken several more months and instances of either Tokoyami, Dark Shadow, or both having 'falling' episodes before they'd found the right term for what was happening, one that actually felt right. Age regression, a coping mechanism to deal with stressors in a healthy manner.
Now Tokoyami was ten years old, and Dark Shadow had become his protector and kept his parents from finding out he'd discovered a Transformative aspect to his Quirk, making it Mutant, Emitter, and Transformation all at once. Neither Tokoyami nor Dark Shadow knew how his parents would react, they'd already threatened to leave Tokoyami at an orphanage because his Quirk didn't fit neatly into a single category and they didn't like that part of his Quirk was sentient as well.
Now Tokoyami was twelve years old and being told to think about what he wanted to do in life, he had to prepare for his future career. He and Dark Shadow had been regressing for three years, and Tokoyami's parents hadn't realised.
Now Tokoyami was fourteen years old and high school exams were right around the corner, he had to make sure he and Dark Shadow were ready for Yuuei and its Hero Course exam. They couldn't afford to fail. He and Dark Shadow had been regressing for five years and had accumulated supplies that were easy to hide from his parents.
Now Tokoyami was fifteen years old and locking himself in his room after the USJ incident so he could regress and deal with the stress without accidentally hurting himself.
Now Tokoyami was fifteen years old and making his first friends that didn't think he was a freak for having a Quirk that didn't fit neatly into one category.
Now Tokoyami was fifteen years old and both he and Dark Shadow needed to regress to cope with the training camp fiasco where Bakugou was kidnapped and they and their classmates nearly died.
Now Tokoyami was fifteen years old and being told dormitories had been built as a measure of protection for the students. His parents signed off on him going before his homeroom teacher even finished asking the question, as eager to get rid of him as he was to have somewhere to call home for once. He and Dark Shadow had been regressing for nearly six years, and the regression supplies were the first things packed for the dorms.
Sippy cups, pacifiers, bottles, stuffed animals, soft blankets used in making nests, clothing that matched Tokoyami's goth aesthetic but was somehow still childish in nature, and toys that Tokoyami had bought off the internet, easily playing the packages he was receiving as gifts from friends (that he didn't have). Juice boxes and a minifridge for snacks were also packed, and Tokoyami moved on to packing the rest of his things.
Now Tokoyami was fifteen years old and arriving at the dorms after all of his things had been brought to his room, and was informed that his classmates had gone and rescued Bakugou themselves despite being told it was under control and being handled. He and Dark Shadow hadn't regressed since a week before the training camp, and resolved to do so once he could be alone in his room. The stress kept piling up, making it to where both might regress to the smallest they could get just to feel like they were at least a little bit okay when they came out of littlespace.
"Fumi? Can we play now?" Dark Shadow asked when they'd retreated to their room, and Tokoyami relaxed after locking the door behind them.
"Yes, my friend. We can play now." Tokoyami said, feeling as his beak grew smaller until it could barely be called such, feathers turning from sleek oil-black to downy grey and receding from his face.
It was the only physical change that signalled Tokoyami going into his headspace, and the bird-Quirked boy let loose the smallest of laughs as Dark Shadow grabbed one of the toys Tokoyami had packed, shaking the little skull-decorated rattle at the boy playfully. The regressed boy, at a mental headspace of a year old, made to grab the toy from Dark Shadow with a childishly innocent smile.
"Do you want the toy, Fumi?" Dark Shadow asked, teasing the other by moving the rattle closer and pulling it away when Tokoyami reached for it.
Tokoyami gave a quiet little giggle, always finding it easier to let his emotions show when he was in his regressed state and able to find joy in things easier. This was a game he and Dark Shadow took part in often, teasing each other with toys when only one of them was regressed. It brought a sense of joy to the little and was humourous to the caregiver, which made it all the more fun for both.
"You almost have it, hatchling." Dark Shadow crooned softly, holding the rattle just out of Tokoyami's reach so the little would try again.
After another moment or two of the teasing, Tokoyami finally got ahold of the rattle and began shaking it a bit happily, almost sticking the end with the beads in his mouth before Dark Shadow stopped him.