Here is the full list of all 18 SEX with HITLER: WW2 achievements.
Complete seventh level
Use the grenade 10 times
Unlock all weapons
Complete sixth level
Use a grenade
Unlock all perks
Pick up the first aid kit 10 times
Kill 400 enemies
Complete fourth level
Pick up ammo 10 times
Kill 250 enemies
Complete second level
Kill 150 enemies
To die for the first time
Kill 50 enemies
Kill 20 enemies
Start the game without purchasing
Use the grenade 25 times