Here is the full list of all 19 Blue Rose achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Completed Gavin route
Completed Tobias route
Completed Simon route
Completed Erin route
Completed Aran route
Reached a Good ending
Reached a Bad ending
Completed all endings
Found the town hidden in the mountains
Was reunited with Simon
Uncovered Adale's treachery
Took part in the festival celebration
Defeated the dragon
Read mini story 1
Read mini story 2
Read mini story 3
Read mini story 4
Read mini story 5
Was reminded of the old fairytale