you can try "make me bark"
http://www.mangago.zone/read-manga/make_me_bark/?YXvs
http://www.mangago.zone/read-manga/a_paramour/
http://www.mangago.zone/read-manga/cherry_blossoms_after_winter/?Nx91
http://www.mangago.zone/read-manga/a_man_like_you/?NdvX
http://www.mangago.zone/read-manga/my_darling_signed_in/?7jV2
http://www.mangago.zone/read-manga/the_devil_s_temptation/?k6Og
http://www.mangago.zone/read-manga/tale_of_the_yellow_dragon/?pBKW
http://www.mangago.zone/read-manga/dear_door/
http://www.mangago.zone/read-manga/puppy_love_eumnya/
http://www.mangago.zone/read-manga/lack_of_love/
http://www.mangago.zone/read-manga/voice_of_love/?k0IC
(hope there is something you havent read yet)
my darling signed in
anyone know any bl manga/manhwa with grey haired seme