SPOILER WARNING DO NOT READ IF YOU WANT TO GET THE ACHIEVEMENTS BY YOURSELF
Avoid Disaster : You must have a good relationship with Claire and do not meet your secret admirer when she gives you the letter. There are other ways of getting this ending but I can't remember any more
Saved fellow IT worker : keep helping Clear Sky Bank's database until you reach level 3 in their database (buy the database book to increase the speed in which you gain levels)
Met Mystica : Go to the park during the even and instead of reading a book, investigate the forest. To see her immediately, choose "I promise" but you can still meet her even if you choose to not keep the promise if you visit the forest the next day or choose to see your secret admirer
Broke the Bank : Just don't help Clear Sky Bank at all to get this
Discovered Identity of Player : When Rina asks to date you, choose "no" and she will give you a computer after a few days. Make sure you've visited Alex in the Cosplay Cafe to increase your relationship with him and he will check the computer out. After the scene, visit the Cosplayer Cafe a few more times and Alex will tell you who the player is
Sophia Chatter: Just talk to her a lot
Sole Survivor: You should train yourself up to get this ending. It's tricky to get, but I think you reject Claire and have a bad relationship with Rina. I think you refuse to see your "secret admirer" to get this. (if anyone knows exactly how to get this please let me know. I've totally forgotten)
Face Yourself: Have a bad relationship with Claire (and an ok one with Rina).
get the spell you need
and go out with Rina in the end.
Glitch: Follow the "face yourself" achievement to get this ending
Saved Claire : Just keep a good relationship with Claire and don't confront her about her boyfriend. Just talk about things that are unrelated to him and when she asks you out, accept her.
Uncovered Mystica's True Identity : See your "secret admirer"
. Refuse her repeatedly and don't promise her anything
. You will battle her. The spell you need is "Dispell"
Truth of Darkness : Follow the "Uncovered Mystica's True Identity" and when you face the shadow, keep attacking it with your physical attacks (no magic. Must train to be able to hit it ). Must defeat the shadow before
Source of Darkness: Same as "Truth of Darkness"
Discovered the Secret of Alex : Follow the "Find the Identity of the Player" achievement. Must get the computer
Sad End : When faced with Claire, either say goodbye to her or don't learn Final Strike
The remaining 2 achievements I couldn't get. (Another Rina and Secret of the Forest). If anyone knows how to get those I'd love you forever!