So sad to see that the story was dropped right when the plot was going to get traction (with the confession). Like, damn… Sumiko, you had something there. But maybe it didn’t work for the author and we gotta respect it.
For those who don’t know the author, currently they are working on “The Guy She Was Interested in Wasn’t a Guy At All”. It’s a weekly twitter series (so 4 pages per chapter) that comes out every Sunday. Besides that series, the author hasn’t been posting anything else, so any other series by them (such as this one, from their pixiv) are probably on hold or have been dropped by the author.
However, there is a 40-chapter (completed) long strip comic by them:
https://www.comico.jp/comic/7318
It seems like a love-triangle situation. Maybe some similar vibes to this story (Girl’s Love, Male Character involved), however not as serious because you can notice Sumiko’s comedic tone in the art style, just like in the Green background series, with the characters faces and the likes.
Couldn’t read it all since I don’t speak japanese, but if anyone wishes to pick it up… Maybe Yuri Project can.