Here is the full list of all 39 Gal*Gun: Double Peace achievements.
Unlock All Trophies
Obtain All Images in the Gallery
Complete Profiles for Every Girl
Defeat 100 Demon Girls
View All of the True Endings
View the True Love Route's True Ending
Receive a “Perfect!” Score VS Patako
View Patako's True Ending
Make 50+ Girls Experience “Double Peace”
Receive a “Perfect!” Score VS Kurona
View Kurona's True Ending
Receive a “Perfect!” Score VS Ekoro
View Ekoro's True Ending
Receive a “Perfect!” Score VS Mr. Demon Balloon
Collect All of the Panties From the Changing Room
View Sisters Route's True Ending
Receive a “Perfect!” Score VS Shinobu & Maya
View Aoi's Ending
Receive a “Perfect!” Score VS Mr. Demon Veggie
Get a Perfect Score on “Demon-Attracting Balm”
Get a Perfect Score on “Sisters' Odd Ritual”
View Maya's True Ending
Receive a “Perfect!” Score VS Maya
Get a Perfect Score on “Maya's Medical Care”
Get a Perfect Score on “Maya's Demon Calling”
View Shinobu's True Ending
Receive a “Perfect!” Score VS Shinobu
Achieve Godlike Rank
View Your First Ending
Experience Your First Final Doki-Doki Mode
Give 500 Girls Euphoria
Fulfill 10 of the Girls' Requests
Get a Perfect Score on “Her Majesty Shinobu”
Fire 1000 Pheromone Shots
Get a Perfect Score on “Shinobu in the Window”
Get 100 Ecstasy Shots
Get a 30 Combo of Ecstasy Shots
Experience Your First Doki-Doki Mode
Give a Girl Euphoria