An altered version of chapter 87, Volume 20
Akutagawa feels anything that Rashomon feels.
Nobody really knew that, he never thought anyone needed to know anyways. He didn't know that he should have told someone, that someone was Atsushi.
Him and Atsushi fought Fukuchi on a ship in the middle of the lake. They thought they won, severing his arms so he couldn't fight. He died there as Atsushi took the Page from his pocket. That is, until Shinto Amenogozen (the ancient swords name) cut through time and altered the past so that instead Atsushi's arm got cut off.
"You damn fool. Hurry up and go. Even if every bone in my body must be broken, I will defeat him. Because if I don't, I'll go back to being something Dazai discarded!” Akutagawa said, wrapping Atsushi in the coat version of Rashomon. He still had his shirt he could use to fight Fukuchi with Rashomon, he just wanted to make sure Atsushi was going to live. In that moment, he could feel Rashomon embracing Atsushi as he pushed him away.
He knew this was a losing battle, now by himself, especially because he was using part of his energy to keep Rashomon around Atsushi as he fled. He knew that would be the last thing he would say to Atsushi.