For this ending I will write exactly what choices I made and where, if when you are playing through you get to a choice that isn't listed below, it's because it didn't matter to the outcome for the trophy so I left it out.
*** Spoiler - click to reveal ***Lesson Choice: I always used MATHS CLASS
[04/11] Join the student council.
[04/15] Vice president.
[04/21] Talk to Sakuya.
[05/21] Cheerleaders.
[06/12] Side with Sakuya.
[06/22] Go to the store.
[06/22] I think that's a little rude!
[07/07] Become a famous artist.
[07/07] No, thank you!
[07/11] Probably Sakuya.
[07/20] You help too!
[07/24] Forget it.
[08/06] Invite Sakuya.
[08/30] Return to my glorious abode.
[09/25] Invite him.
[11/10] Go look.
[12/24] Go to the party.
[12/24] Stop him.
[01/01] Fulfillment in art. (If you don't get this flag, do not worry, it isn't important.)
[02/02] Racing blend.
[02/12] I loved.