it's @mijinko01417, they have another manga and another works in several haikyuu kareshi doujinshi
Name of another manga?
TUANK YOUUUUISUSHWHWHAJWKAHSJWJDKWKFKWKLTEOFKEOFKLR
it's already here, idk why it's not listed together
https://www.mangago.zone/read-manga/how_i_the_royal_spy_won_over_five_princes/
you're welcome! also @mijin_combi popped up when i search for their webtoon works, ig they have separate account for each genre? also there's private one from their doujinshi work era idk i'm so confused now lololol
does anyone know this artist's twitter? their art looks sooo good