Here is the full list of all 69 DEEP SPACE WAIFU: FANTASY achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
SEE THE CREDITS!
RESCUE THE PRINCESS FIERNA
EXPLORE ALL OF THE HENTALIA CONTINENT
100% AUGEMEISTER
FIND THE CLITORIUS
100% SONJA DRAGONTOOTH
DEFEAT BRAINHOLDER
YOU ENTERED GALLERY MODE
DEFEAT THE MOAI ANGEL
100% OPHELIA
UNLOCK OPHELIA
DEFEAT THE UGLY FAERIES
100% NORMAL RYA TUTORIALICCA
REACH STAR LEVEL 35
DEFEAT THE KNIGHT SKULL
100% TIA SOFTHAND
UNLOCK THE SWORD ABILITY
UNLOCK AUGEMEISTER
UNLOCK THE DRAGON
DEFEAT SATAN
100% METAL ABYSSAL
UNLOCK THE EXTRA SHOOTING POWER
UNLOCK SONJA DRAGONTOOTH
REACH STAR LEVEL 25
DEFEAT THE SLIME SUB BOSS
100% JELLY-CHAN
DESTROY THE ANGEL MINIBOSS
UNLOCK THE FILLED SPECIAL BAR
FIND A RANDOM ENCOUNTER
DEFEAT ASMODEUS
100% TRICCIA
UNLOCK THE EXTRA POWER UP SLOT
UNLOCK TRICCIA
UNLOCK NORMAL RYA TUTORIALICCA
UNLOCK THE UNICORN
REACH STAR LEVEL 15
DEFEATS TENTACLE MOON
100% OROCHI THE NAGA
UNLOCK THE BANDANA
UNLOCK THE PROTECTIVE HELMET
UNLOCK TIA SOFTHAND
REACH STAR LEVEL 10
SKIP ONE OF OUR EMOTIONAL CUTSCENES
UNLOCK METAL ABYSSAL
GET 5 STARS IN ONE STAGE
UNLOCK OROCHI THE NAGA
DEFEAT VIKING
100% CARSSIA BORGOTH
REACH STAR LEVEL 5
UNLOCK CARSSIA BORGOTH
TAKE A PICTURE OF A GIRL IN MIDDLE AGES
DEFEAT THE DEVILANGEL SUB BOSS
100% RENA GREENLEAF
DESTROY THE DEVIL MINIBOSS
YOU DIED IN A DATE
EXPLODE A PIECE OF CLOTH
HAVE YOUR FIRST DATE
PRESS START
COMPLETE ONE HAND SONJA
COMPLETE ONE HAND AUGEMEISTER
COMPLETE ONE HAND MODE CARSSIA
COMPLETE ONE HAND MODE OROCHI
COMPLETE ONE HAND MODE TRICCIA
COMPLETE ONE HAND ABYSSAL
COMPLETE ONE HAND RYA
COMPLETE ONE HAND OPHELIA
COMPLETE ONE HAND TIA SOFTHAND
COMPLETE ONE HAND MODE RENA
COMPLETE ONE HAND MODE JELLY