i've been wondering for a long time now under what circumstances the dolorosa was reborn as a rainbow drinker, since it's heavily implied to require 1. significant sunlight and undead exposure and 2. a death that doesnt destroy the body. given the ancestors who were around then, and the lack of doc scratch or other ocmments indicating DS interfered with her like he did kanaya, and kanaya's kimonos indicating the influence, my bet is the handmaid killed her to complete the metamorphosis

I’m not sure all of these assumptions are necessarily correct.

While it’s true that the comic implies rainbow drinkers are to some extent fueled by sunlight, Kanaya and Porrim seem to believe that many rainbow drinker traits are natural jadeblood adaptations to living in the brooding caverns. From A6I3:

KANAYA: Im Told Its A Trait Confined To Those Of My Caste
KANAYA: They Tended To Spend A Lot Of Time In The Brooding Caverns Where A Convenient Source Of Light Was Often Handy

I’m more of the belief that rainbow drinkers being confined to the caverns weakens their powers, rather than outright prevents them from transforming.

In any case, the Dolorosa banished herself from the caverns after taking in the Signless, so she would have had plenty of access to sunlight subsequent to that.

I don’t think Kanaya’s connection to Japanese culture need to be so convoluted; her Japanese-style items of clothing probably simply connect to the fact that, like Damara, she was a protege of Scratch’s.