It's not extremely detailed but I always remember this scene bc well, idk it's in a movie theatre what can u expect?
http://www.mangago.me/read-manga/window_beyond_window/uu/window_beyond_window-chapter-30/2/
https://myreadingmanga.info/nishida-mizuki-kun-no-ero-manga-days-dj-eng/
it's a doujinshi but you don't need to know anything about the characters lol.
http://www.mangago.me/read-manga/the_double_life_of_the_demon_king/
There are some hot BJ scenes in this
Recommend me the best blow job scenes from any BL (▰˘◡˘▰)