Here is the full list of all 32 Nyasha achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Megumi Normal
GameOut
Yoko Normal
Shinju Hight
Hikeru Hight
Tomiko Hight
Nori Hight
Michie Hight
Megumi Hight
Keoru Hight
Yoko Hight
Aki Hight
Arizu Hight
Shinju Normal
Hikeru Normal
Tomiko Normal
Nori Normal
Michie Normal
Keoru Normal
Aki Normal
Arizu Normal
Shinju Easy
Hikeru Easy
Tomiko Easy
Nori Easy
Michie Easy
Megumi Easy
Keoru Easy
Yoko Easy
Aki Easy
Arizu Easy
GameOn