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 Easy
Shinju Easy
Hikeru Easy
Tomiko Easy
Nori Easy
Michie Easy
Keoru Easy
Yoko Easy
Aki Easy
Shinju Normal
Hikeru Normal
Tomiko Normal
Nori Normal
Michie Normal
Megumi Normal
Keoru Normal
Yoko Normal
Aki Normal
Arizu Normal
Shinju Hight
Hikeru Hight
Tomiko Hight
Nori Hight
Michie Hight
Keoru Hight
Arizu Hight
Megumi Hight
Yoko Hight
Aki Hight
GameOut
Arizu Easy
GameOn