"So, here's what I got.
Kageyama Fumiya got involved in a fight and was stabbed and dumped in a river. A woman who's mentally ill got him, drugged him, and confined him, believing he's her lost son.
During the time Kageyama is missing, his prosecutor friend, Hiura, kept looking for him and met Naoto, Fumiya's brother. Also, during this time, Fumiya's spirit kept on going to Hiura and appearing in his and in his room. There were also times wherein Fumiya possessed Naoto'-s body to talk to him and even had sex with him.
After searching high and low for Fumiya, Hiura finally got a lead and was able to rescue Fumiya. He was hospitalized but able to recuperate.
The ending was rather ambiguous since it wasn't clear whether Hiura's approach to Fumiya was as a friend or as a love-interest. Though it was shown earlier that Hiura was also longing for Fumiya.
The extras were flashbacks of the two's university life." he got possessed???? the spirit thing was real????? I need to read this again when I'm not in a brain fog
Yoru ga Owaru Made