This Onmyoji is Bad News(2008)

Ikenai Onmyouji

Haruki, a 17-year-old high school student, is the heir to the Sanmon Mamoru family and an Onmyoji by profession. He has a nasty constitution that attracts monsters. Haruki's distant relative Mutsuki, another Onmyoji, supports Haruki in the shadows as his guardian and protector, but he is actually hiding an unbelievably dark side...? In addition to the title story, there is also a extra short story about a sexually harassed priest, "Dangerous Onmyoji."

(Source: Kadokawa)