this is actually just a test drawing
I was adjusting a brush for a friend based on the grunge looking pen on Gachiakuta
(you can try it if you like, its for ClipStudio, far from perfect, the link will be up til oct 7)
fromsmash.com/Grunge-pen

it was mostly pink at first but all the pink became orange after i added the yellows...

first i sketched it very loosely, then i used some of these water brushes, filled them with magenta, cyan and yellow inks each, start playing around until it took form, do the lineart with a brush with red ink, then start adding dimension with prismacolors, and lastly layer it down with acrylic pens

scan and the pic of the original