A good yaoi with side character spin off series thank you ahead of time!

http://www.mangago.me/read-manga/xxx_allergy/

http://www.mangago.me/read-manga/secret_xxx/
and spin-off :

http://www.mangago.me/read-manga/therapy_game/

http://www.mangago.me/read-manga/therapy_game_restart/

http://www.mangago.me/read-manga/ookami_papa_wa_hitsuji_tsura_shite_yatte_kuru/
spin-off :

http://www.mangago.me/read-manga/sensei_wa_butchozura_shite_yatte_kuru/

http://www.mangago.me/read-manga/drugless_sex/
spin-off:

http://www.mangago.me/read-manga/drag_less_sex_2_tatsumi_to_inui/

http://www.mangago.me/read-manga/abarenbo_honey/
spin-off:

http://www.mangago.me/read-manga/amaenbo_honey/

http://www.mangago.me/read-manga/akai_ito_no_shikkou_yuuyo/
spin-off:

http://www.mangago.me/read-manga/kanawanu_koi_no_musubikata/

Hitorijime my boyfriend
Hitorijime my hero

The spin off is less good tho in my opinion

Thank you all!