Guys! do you know any yaoi manga that have sex scene in every chapter with the the same co...

The only one coming to my mind right now is - http://www.mangago.me/read-manga/porno_superstar/
You should also try the Kuroneko series by Sakyo Aya if you haven't yet.

with have sex scene in every chapter?? Woahh,... it's hard to find,..

but, I am Sorry,... maybe this is not that..

http://www.mangago.me/read-manga/okane_ga_nai/
http://www.mangago.me/read-manga/rutta_to_kodama/
http://www.mangago.me/read-manga/17_sai_no_hisoka_na_yokujou/
http://www.mangago.me/read-manga/doushitemo_furetakunai/
http://www.mangago.me/read-manga/katekyo/
http://www.mangago.me/read-manga/gokujou_no_koibito/
http://www.mangago.me/read-manga/crimson_spell/
http://www.mangago.me/read-manga/mankai_darling/
http://www.mangago.me/read-manga/kuroneko_kareshi_no_asobikata/
http://www.mangago.me/read-manga/haru_wo_daite_ita/
http://www.mangago.me/read-manga/himegoto_asobi/
http://www.mangago.me/read-manga/kuroneko_kareshi_no_nakasekata/
http://www.mangago.me/read-manga/sugar_code/
http://www.mangago.me/read-manga/under_grand_hotel/
http://www.mangago.me/read-manga/elektel_delusion/
http://www.mangago.me/read-manga/hidoku_shinaide/

In about 85% of the chapters they have sex. http://www.mangago.me/read-manga/kobi_no_kyoujin/

http://www.mangago.me/read-manga/kichiku_encount/
I kid you not, all they ever do is have sex. Her another mangas as well.

Off the top of my head I can only think of the following:
http://www.mangago.me/read-manga/katekyo/
http://www.mangago.me/read-manga/haru_wo_daite_ita/
http://www.mangago.me/read-manga/kokoro_kanda_neko/
http://www.mangago.me/read-manga/kichiku_encount/
http://www.mangago.me/read-manga/hisho_ikuseichuu/
http://www.mangago.me/read-manga/aijin/
http://www.mangago.me/read-manga/darling/
http://www.mangago.me/read-manga/kare_no_shousou_to_koi_ni_tsuite/

i am collecting them here. actually, there's a lot of manga that is like that. check those that i especially laballed as 'smutty' manga. http://www.mangago.me/home/mangalist/50912/ a lot of manga in this list are usually long with sex scenes on each chapter.

Room to Room

Absolutely right they're all short and good too