Sunny Day
Another one of my older guro stories.
Rei isn't hungry, but doesn't want to just sit there waiting for Shinji to finish his meal, so she chooses a random item from the entertainment section of the menu to kill time… and herself.
The 1st chapter is about Shinji and Rei and focuses on garotting Rei. Just a brief mention of besitality and no scat here.
The 2nd chapter is about Touji and Hikari and focuses on beating Hikari with a baseball bat, but also includes some bestiality and a little bit of scatophagy.

Read on AO3
English: https://archiveofourown.org/works/15601050