Stigmata
https://www.mangago.me/read-manga/noufu_to_shinpu_the_farmer_and_the_priest_eng/ - This is pure porn btw.
https://www.mangago.me/read-manga/furyou_shinpu_ni_yoru_hatsujou_kyuuketsuki_no_shitsukekata/ - Priest x vampire
https://www.mangago.me/read-manga/sex_therapist/ - Ch 7, priest x priest.
https://www.mangago.me/read-manga/omairi_desu_yo/ - buddhist priest x old unrequited love.
https://www.mangago.me/read-manga/platinum_blood/ - Another vampire x priest.
https://www.mangago.me/read-manga/stigmata_1/ - Has a priest with religious undertones.
https://www.mangago.me/read-manga/the_prefect_s_private_garden_8232/ - Not like super religious I'd say but Tsukihito is treated as a god/worshipped as something of a savant. The story is also pretty dark and twisted, just a heads up.
....i know what you areeeeeee FREAKYYYYYY!! THANKYOU FOR FEEDING ME
You know me well (⌒▽⌒) Enjoy!
Religious themes BL?