- Squick: Should be the name of the theme song to this novel. Ayaka Sasaki has her intestines ripped out of her abdomen and is forcefully strangled by them.
- Tear Jerker: A Lullaby Sinister is full of moments for feels. More notably, Satoshi having to put his girlfriend out of her pained misery after being tortured. Kaito's last minute confession of love to Misa before the two are obliterated is another example, made worse by the fact that he didn't confess to her earlier because he refused to hold her back.
- The Woobie: Yunosuke Kawabata. A majority of the time, his character exists for comic relief, especially with his perverted misadventures with Sadako Kojima. While his actions are not innocent, Yunosuke comes across as the type of person who simply does not know any better. At a pivotal point, Yunosuke finally chooses the noble thing to do and sacrifices himself to save Sadako from See No Evil. Unfortunately, Sadako has no recollection of this because of the Surrogate School's amnesia and still refers to him negatively.
YMMV / A Lullaby Sinister