from what i had in mind when drawing this is, nea reincarnated after some hundreds years, and suddenly is Road’s new classmate and blabla now he’s in front of cornellia again (and allen is there reminiscing the past hoho)
this is a great question, but the answer is most likely neither! while it’s justifiable for allen’s hair to turn white due to trauma, that usually occurs over a period of time while cross had already approached allen after the incident with his hair already changed. the curse has shown to have no effects on allen’s body minus the immunity to akuma poisons, so the culprit is likely his innocence.
i believed it was confirmed for some parasitic types, or at the very least in timothy’s case that the change occurs once invoking properly for the first time. timothy is a prime example for this, as he had usually a full head of brown hair before he awakened tsukikami during the theif g arc and transformed into his signature pale blue style. i believe it was even confirmed by the characters themselves that innocence was the cause in one of the info books but i couldn’t find the source at the moment.
it was said at the last volume’s talk corner!
Timothy talked about how Allen tried to dye his hair but it just turned back to white, so it must be the Innocence’s doing!
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