http://www.mangago.zone/read-manga/hitori_to_hitori_no_3650nichi/
it's pretty much angsty
Anything Harada, istg
Dark Heaven
Try some Echo Jiro mangas
How to kill a heart by Kashio
Ogawa Chise works
Psyche Delico works
Harada
Ten Ten Shiro Shiro
Nishin Masumi works
Asada Nemui works
Nakamura Asumiko
Kuraka Sui
Ido Gihou
Can someone recommend me non-manhwa dark yaoi?