These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
What Do You Mean, It's Not Symbolic?: The manga has some Judeo-Christian symbolism going on just for the fun of it (e.g. "Sheravy" is obviously a corruption of "Seraphim", the top-ranked angels).
The Woobie: Suou. After seeing Akane, the person who matter the most to her in her life die, she finds that nobody her school knows who she is. She finds that she has some scattered memories, but what happened was her mother was executed from crimes against the demon royal family, and she was to be executed before Creo brought her to Earth and left her there, despite the two become extremely close. Akane was created to protect Suou, and all the memories Suou had of growing up in the human world and everyone there had of her were an illusion Akane created, which faded after she died. This means the only person she has left is Creo, and then both go back to the demon world, Creo gets nearly killed for protecting Suou.