Koumyou nods, miserable. And says a quiet, muffled, "I'm sorry."

They've hopefully managed to not damage the wedding, but... Devero had been having a good time, and now...

Well, it's further proof of how unsuitable Koumyou is, isn't it?

He repeats it quieter, too, "I'm really sorry."

Dev should have someone who can keep him out of his own despair, not someone who will drag him down into theirs! Devero deserves to always be happy, and to stay happy. He's gone through enough misery!