
lol author just wants another drama cuz everything's going fine for everyone and shizu and hiragi needed some misunderstanding between them for their pair to develop so what did the author do? *Shoves yuki into the picture*
gawd, just let the boy die in peace lol

Actually, it was almost clear from the beginning (When Hiragi showed up in the Manga), that he had feelings for Yuki. Just need to see how Hiragi always looked at Yuki, or both Yuki and Mafuyu when they were together.
This is not a misunderstanding from Shizu's side, he talked in the past form: "You were".
The Author also didn't shove Yuki in to the picture, because he was always there too. Not physically of course, but Yuki is the reason for everything. The reason for the story. I mean, I understand what you meant, but think about it. Everything happens, or better said, everyone behaves in a particular way, because of Yuki.
Yuki is the like a shadow, or a curse. Even though he is dead, mostly everything happens because of him.
I am more annoyed about other things to be honest. Like the nonexistence of common sense. Like, Mafuyu drives his Boyfriend to commit suicide, but was never really guilty about it. I mean, I don't remember having read how Mafuyu had a bad conscience or something. Even because 6 months passed, and he already had another guy. Now he is being jealous and is afraid he will lose Ue, to the other guys, and that he will be left alone again, which is also the reason why he is afraid of going pro. BUT, he never thought that "I fought with my ex-boyfriend because he prioritized the Music, in which I was not interested in, over me. Drove him in to committing suicide by saying, "go die for me", but now I am doing the same thing, and also thinking of going pro". Do you understand what I am trying to say?
The logic in this Manga, is somewhat messed up. Even the other couple. Big logic issues, in my opinion.

AHHHHH THE EXTRA IS SO CUTE
This is the first time I re-read an omegaverse so many times,, I am confident to say that this is the most perfect omegaverse I've read. Nothing is forced and it's full of the right balance of fluff and drama ⊂(´・◡・⊂ )∘˚˳°

I recommend reading:
http://www.mangago.zone/read-manga/tadaima_okaeri/
its a fluffy Omegaverse
The plot is pretty basic but the smut scenes are amazing and it's still vanilla but with a hint of bdsm in it which makes it different from other yaois,,, idk how to describe it but it's kinda like that