Artist:

The words Koah is writing are from a traditional Ukrainian military song, "In the meadow, a red viburnum", and the spirt of the words are:
"And we shall cheer up our glorious Ukraine!"

This drawing was inspired by Andriy Khlyvnyuk The Kiffness remix, which is available here: https://www.youtube.com/watch?v=lu8m5FA2nL8 - All royalties from the video will be donated to humanitarian aid for the Ukrainian armed forces.

P.S. The embroidery on Koah's jacket is of the titular red viburnum - a Ukrainian national symbol.