Here is the full list of all 48 Just Deserts achievements.
Complete Yumi route
Complete Eve route
Complete Cornelia route
Complete Jennifer route
Achieve “Harem” End
Use Cornelia's Spear Fall support 4 times in 1 game
Win in 1 turn, 5 times in 1 game
Give 30 packs of instant noodle
Give 20 disliked items to 1 heroine in 1 game
Give 10 disliked items to 1 heroine in 1 game
Give 30 erotic items
Has 0 Bz money
Sleep in the morning for 20 days in 1 game
Sleep in the morning for 10 days in 1 game
Sleep before night for 5 days in 1 game
Complete 1 game (1 route)
Complete Cecile route
Use Cornelia's Spear Fall support in a battle
Workout 30 times in 1 game
Talk 50 times
Buy 100 items
Shooting Practice 30 times in 1 game
Have a meal 30 times in 1 game
Swimming 30 times in 1 game
Die before day 2
Talk 300 times
Achieve "Love" relationship with all heroines in 1 game
Achieve "Infatuated" relationship with all heroines in 1 game
Reveal all character’s talk lines
Kill 30 aliens with hand gun in 1 game
Defeat 50 aliens in 1 game
Defeat 150 aliens in 1 game
Run from battle 30 times in 1 game
Use medicine 25 times in 1 game
Win 5 battles each in less than 4 turns in 1 game
Buy 30 bottles of mineral water in 1 game
Buy 25 teddy bears or 25 polar bears in 1 game
Get a Lucky Pendant
Get money for the first time
Reach 1,000,000 Bz cash
Reach 5,000,000 million Bz cash
Complete 40 Patrol Works in 1 game
Complete 30 Quests in 1 game
Complete all game routes
Passed out 10 times in 1 game
Achieve "Single" End
Reveal all CG
Reveal all story