Series timeline
1) Yakuza-sama no Omocha (main story) (Ogiwara meets & falls for yakuza head,Saki )
>>>2) Koyoi wa Tengoku (sequel) (Ogiwara X saki dating life, one shot)
3)Hana no Akuta (Spin-Off) (undercover investigator ,Tsubaki X yakuza heir,Kajiro)
4) Charmed Straight to Hell (undercover investigator ,Tsubaki X yakuza heir,Kajiro)
5) Charmed Straight to Hell 2 (undercover investigator ,Tsubaki X yakuza heir,Kajiro)
6) Charmed Straight to Hell 3 ~Love Hotel Punishment~ (undercover investigator ,Tsubaki X yakuza heir,Kajiro)
Just smut of main couple
Koyoi wa Tengoku