Here is the full list of all 15 My Klutzy Cupid achievements.
Reached Uta's ending.
Obtained all achievements.
Reached Kotohina's ending.
Started Kotohina's route
Started Uta's route
Reached Eil's ending.
Started Eil's route
Reached Isuzu's ending.
Started Izusu's route
Reached Rinka's ending.
Started Rinka's route
Reached Masora's ending.
Reached Kururu's ending.
Started Kururu's route
Started the game