Anything by Harada is usually really smutty, this is my favorite by her
http://www.mangago.zone/read-manga/yatamomo/
if ur looking for super smutty djs (with no romance, just all smut), go with gamushara mob rape, fakkyuu something something orc something (sry can't remember the title but it should come up if you search it tho it's on myreadingmanga, not here), any of kuroquis' haikyuu djs are also reALLY smutty. basically, if you go on myreadingmanga, there's a multitude of djs that are porn without plot.
as for non-dj yaois (i'll link these):
http://www.mangago.zone/read-manga/ookami_san_to_eroi_koto/
http://www.mangago.zone/read-manga/yotta_ikioi_de_hotel_ni_tsurekomare_josou_shita_otoko_ni_nazeka_ore_ga_horareru_hanashi/
http://www.mangago.zone/read-manga/tonde_hi_ni_iru_natsu_no_neko/
http://www.mangago.zone/read-manga/ai_subeki_sadist/
http://www.mangago.zone/read-manga/otoshiana_ni_hamerarete/
http://www.mangago.zone/read-manga/ichimai_goshi_fetish/
http://www.mangago.zone/read-manga/kawaii_obaka_kun/
http://www.mangago.zone/read-manga/zattou_ni_asobu_sakana/
http://www.mangago.zone/read-manga/afurete_shimau/
http://www.mangago.zone/read-manga/kichiku_encount/
http://www.mangago.zone/read-manga/porno_superstar/
http://www.mangago.zone/read-manga/calling_ootsuki_miu/
http://www.mangago.zone/read-manga/kabeana_money_hole/
http://www.mangago.zone/read-manga/kabeana_heaven_hole/
Someone recommend me some hardcore yaoi???