Out of boredom, I decided to try and find every ending in Memory Days Sim Date by Pacthesis: http://fav.me/d5ay7aj
It took me several hours, but here is what I've found. Feel free to add any additional information in the comments section and I will add it in. If you have any questions about the guide, also direct them into the comments section below.
Endings:
1. Your Next Phone Call End the game with Haru (don't go out on your birthday, start going out on Valentine 's Day, skip week one, don't spend Christmas with him, and don't go on dates. That's what I did.)
2. Happily Ever After End the game with Haru