Here is the full list of all 22 Sword of Asumi achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Completed Death of Hikari Ending
Completed the 'canon' ending to the game
Completed Mercy is for the Weak Ending
Completed the Dying Alone Ending
Completed Hikari's Unrequited Love Ending
Killed Mineko at the End
Killed Utsuro at the End
Suggest to Kaori she is your type too
Saved the World and fell in love #1
Saved the World and fell in love #4
Impress Kami with your poetry skills
Saved the World and fell in love #2
Assassinate the kidnappers after they talk
Try a little cosplay with Kaori
Drug the Principal for Information
Get a perfect score in Tactics with Sen
Came first on the Obstacle Course
Skipped the intro on second playthrough
Kill Everyone in the intro
Completed the entire game at least once
Saved the World and fell in love #3
You Spread Rumours about Hiro & Jiro