Aaaahhh ... LOVE Chitose Piyoko-san's works ! I read this years ago on another site, but ran across it again today, so I will add it to the lists ! Not all the stories here include BDSM, but enough do to make it allowable. Enjoy !
The story with the twins was messed up! The short haired twin was deeply concerned over his long haired twin brother, while the long haired twin hurts him for being better! That was seriously messed up, I feel bad for the short haired twin.
C1 and 2, we'll see our lovely Matsuoka taking care of his cute roommate, Oono. C3 and 4, what does Natsu want from the twins? How does he intend to cleanse the melancholy from the younger twin's heart? Please note that C3 is quite sadistic. Get some tips on the 101 ways of doing it on the dentist chair from Kiyomura sensei and his patient, Takamiya in C5. And finally, learn about the right ways of using a bottle and positioning in C6.
1-2. Tsukiyo no Fushigi 3-4. Melancholy 5. An Appointment Only For You 6. Extreme -