Here is the full list of all 41 SG/ZH: School Girl/Zombie Hunter achievements.
See the ending by beating the game.
Clear Chapter 5.
Defeat a total of 5,000 enemies.
Undress 3 people during a single mission.
Obtain all shoes.
Obtain shoes for the first time.
Defeat all Charons and then clear any mission.
Clear Chapter 4.
Defeat Die Jaeger by yourself in an offline mission or hosted online mission.
Clear Chapter 3.
Clear a Boss mission for the first time.
Obtain 50% of all weapons.
Clear Chapter 2.
Undress for the first time.
Defeat a total of 1,000 enemies.
Clear a Timed Survival mission for the first time.
Clear a Fetch mission for the first time.
Clear Chapter 1.
Use Mayaya for the first time and clear a mission.
Use Rei for the first time and clear a mission.
Defeat all Charons in one mission, then clear the mission.
Use Enami for the first time and clear a mission.
Obtain an oufit for the first time.
Defeat a total of 100 enemies.
Use a Club Attack 10 times in a single mission.
Use a Club Attack for the first time.
Use Risa for the first time and clear a mission.
Defeat Charon for the first time and then clear a mission.
Clear a Destination mission for the first time.
Obtain a new weapon for the first time.
Use Sayuri for the first time and clear a mission.
Clear a mission for the first time.
Attack a zombie's weak point for the first time.
You achieved everything!
Defeat a total of 10,000 enemies.
Obtain all weapons.
Obtain Rank SSS in all offline missions on all difficulty settings.
Obtain all oufits.
Clear all offline missions on all difficulty settings.
Use an Underwear Trap for the first time.
Defeat Ren by yourself in an offline mission or hosted online mission.