Here is the full list of all 24 Learn Japanese To Survive! Katakana War achievements.
Clear the game.
Maximize all character's affection levels.
Obtain the ultimate sword.
Complete all 20 side quests.
Complete 15 side quests.
Complete lesson 10.
Unlock the potential of corn soup.
Try 3 different types of seafood.
Complete lesson 9.
Complete lesson 8.
Complete lesson 7.
Complete 10 side quests.
Complete lesson 6.
Complete lesson 5.
Visit the Challenge Castle.
Complete 5 side quests.
Maximize a character's affection level.
Complete lesson 4.
Unlock the power of the Crystarium
Complete lesson 3.
View a character's affection event.
Complete a side quest.
Complete lesson 2.
Complete lesson 1.