So it has been discussed several times and I think the general consensus is that she represents the Caterpillar in the same way Arisu is Alice, Chishiya is the Cheshire Cat, and Usagi is the White Rabbit. It’s less obvious since her name isn’t a direct reference aside from having the same first sound but her cigarette and proximity to Chishiya while serving the same mostly positive purpose makes it seem that way. With this in mind I realized something- a big part of caterpillars is the fact that they seem like their own creature at first but they turn into a completely different thing (butterfly or moth) which is their true form. I think this could be some foreshadowing of her being transgender. She started out as a caterpillar (pre transition) but then she was able to exit the ‘cocoon’ and become a butterfly! Sorry if this is something commonly known but I was thinking about this earlier today and wanted to post it just in case!