It's from the "Uro-butcher" himself. What did you expect?
All spoilers below are unmarked. Proceed with caution.
- The themes of the game itself are quite depressing. Due to Saya being an Eldritch Abomination and Fuminori's nightmarishly distorted senses, both of them are surrounded by people who they cannot or can barely tolerate interacting with. Both are completely alone in a hostile and alien world. They fall in love, and it forms a bond that is truly unbreakable. Even in the midst of all the Nightmare Fuel, Nausea Fuel, and Moral Event Horizon-crossing, they somehow manage to stay sympathetic characters. Of course, considering the genre, there's really only one way it can end. Bonus points for the second ending's End of the World as We Know It being completely overshadowed by Saya's goodbye, even though said goodbye is what causes the end.
- Suzumi, by all appearances a loving family man and friendly neighbor, killing his wife and child (especially the child, who runs from him in terror). No one is safe in this story and no one gets a good ending.
- Except maybe Fuminori in the ending wherein Earth is conquered by Saya's children, and even that's still some good Tear Jerker considering Saya dies in his arms after giving birth.
- Yoh's last conscious thought after being assaulted by Saya is lamenting that she never had her first kiss.
- The "bad" ending, which is ironically the best outcome for all the characters: Fuminori chooses to return to the way he was before his accident and parts ways with Saya. His senses and morality are restored, but he is locked away in a sanitarium, probably for the rest of his life, for murders he didn't commit and no way to prove his innocence. And although she committed unforgivable acts, one can't help but feel sad when Saya visits Fuminori in the hospital to say goodbye, particularly when she starts crying after Fuminori's Love Confession.
- Fuminori also starts crying when he calls the police out of sheer relief for being able to hear a human's voice again.
- The "Everybody Dies" Ending. It's arguably the best ending for the world at large, since both Fuminori and Saya are dead now, but it's also the saddest, as every character in the game is dead except for Koji, who's still rendered irreversibly traumatized and suicidal.
- The scene where the dying Saya caresses the dead Fuminori's cheek, while Koji smashes her over and over again with a steel pipe, screaming at her to get away from him. It makes you feel awful for both of them; Saya for obvious reasons, and Koji because even after his entire world was turned upside down, he still loved Fuminori - his best friend - and felt the need to protect him, ironically, from the very monster that had kept him going.
