Here is the full list of all 49 The Caligula Effect 2 achievements.
Completed Chapter 1.
Used an Overdose Skill for the first time.
Landed a successful Sucker Punch for the first time.
Completed the Prologue.
Used χ-Jack for the first time.
Answered Regret's call.
Acquired all trophies.
Completed Chapter 2.
Completed Chapter 3.
Completed Chapter 4.
Completed Chapter 5.
Completed Chapter 6.
Completed Chapter 7.
Completed Chapter 8.
Began a second playthrough by loading cleared save data.
Completed a person's Character Episode.
Completed all Go-Home Club members' Character Episodes.
Challenged the Tower of Prometheus.
Made over 100 friends.
Completed the Causality Link chart.
Achieve ★ Affinity with all residents of Redo.
Cleared a Solo Quest for the first time.
Cleared all Solo Quests.
Cleared "Extracurricular Affair."
Cleared "Eat Your Heart Out."
Cleared "Extra! Extra! Journalism Club Showdown."
Cleared "Hustled and Bustled."
Cleared "The Part-Time Tyrant."
Cleared "For the Love of Regret."
Cleared "Prince of Lettuce."
Cleared "Love, Loss, and the Omega Nebula."
Cleared "From Nurse to Worse."
Cleared "Birth of a Salesman."
Cleared all Group Quests.
Obtained all WIRE conversation topics.
Sent a set number of texts on WIRE.
Participated in the lottery for the first time.
Made a transaction using χ Points at the χ Shop for the first time.
Sold a Stigma for the first time.
Attained a total of 10,000 χ Points.
Learned all available skills for χ.
Acquired over 50 Passive Skills for the protagonist.
Landed over 50 successful Sucker Punches.
Landed over 100 successful counters.
Landed over 100 successful Risk Breaks.
Performed over 50 successful guards.
Successfully activated over 200 Trigger Skills.
Won over 200 battles.
Acquired all of χ's cover songs.