Rather than changed, they just improved
I wouldn't say they change their artstyle, I'd say itd just be a more polished/rendered version of their style. Often, authors simplify their artstyle somewhat to make the drawing proccess throughout the main story less bothersome/long and then go all out on titlepage pictures and the after/side stories. Sometimes using black and white colouring can be less time consuming as well. It keeps up an aesthetic whilst also cutting the time of colouring. (other manwhas that did this for example would be BJ Alex, Love Is An Illusion, Fools). Or sometimes the author may feel artistically-cramped after doing the same style for so long and goes all out in experimenting with different techniques for the side/after stories.
I also might add, often side stories can be done many months after the main story, which leaves time for the author to recooperate and practice. They probably learn a few things on their jounrey story telling and want to express it through their side stories.
Ah! Okay, I understand. I just though they changed because it was only extras. Coz in the main Jaeha and Eunho looked a lot more...attractive, (other managa characters as well) and then now they look squishy. It’s cute and all but a bit squishy. Kept reminding me of Haebom from Cherry Blossoms After Winter.
haha i get where your coming from
Why do the authors change the art style of their characters after the main story? Not saying it’s bad or anything, but I do notice this when I read them. Really, genuinely curious. If anyone knows.