Here is the full list of all 15 Kinkoi: Golden Time achievements.
Start the game
Complete the prologue
Start Mina's Route
Finish Mina's Route
Start Ayaka's Route
Finish Ayaka's Route
Start Maria's Route
Finish Maria's Route
Finish Append Sylvie
Finish Append Elle
Finish Append Reina
Finish Append Akane
Finish Append Ria
Finish Append Mina
Get all Achievements