Rachael has PTSD from being bullied herself. She likes certain anime because they offer some emotional solace and show great friendships.
Intro & Summary:
Blue Exorcist centers around twin brothers, Rin and Yukio Okumura. Rin is the older brother, but acts like the younger one, being less responsible and more hot-tempered. Their father is a priest and an exorcist. Eventually, Rin finds out that not only can he see demons, but he is actually the spawn of Satan. So is his brother, but Yukio doesn't have any of Satan's powers, and is an ordinary human.
Their father dies, possessed by Satan. So Rin wants to become an exorcist, and get strong enough to kill Satan someday, and all demons. So he goes to an academy for exorcists. And what do you know, his brother is not only already an exorcist, but Rin's teacher! What?! Sibling rivalry isn't the only kind at True Cross Academy though. Rin soon finds himself at odds with classmate Ryugi, a strong exorcist-in-training who also has the goal of one day defeating Satan. Oh man, who would have guessed that people who are going to a school to slay demons might fantasize about someday killing the ruler of all demons?
Manga by Kazue Kato
25 + 1 OVA episode
Film, Sequel Manga
So it's your standard shounen magical academy plot, but it might have enough references to demons to put Christian parents on edge and make some teenagers think it's cool because said Christian parents might not like it. I mean, the protagonist and his brother are offspring of Satan. But, it's also about a character with a vendetta against Satan and all demons, which might be positive from a Christian perspective. Except there is no real mention of Jesus because this is just a weird Japanese writer's use of Christian concepts such that they only exist in the story relative to their importance in the plot. A cross is there then, not as a symbolic remembrance of Christ's sacrifice for humanity, but as a nifty "edgy", "foreign" symbol that the author knows is often feared by demons in vampire stories, dating back to the original Dracula. You see the same damn thing (pun intended) in Trinity Blood, Helsing, etc. Similarly, the demons here are not about testing people's faith or goodness in the face of crises, like the devil does in The Good Book and in Faust. They're magical monsters with vaguely explained supernatural powers, to be slain by magical heroes known as exorcists. It has about as much real Christianity in it as Naruto has real martial arts. Or less, actually. Just an excuse for another show about punching, flinging magic around, running, and yelling. Can I go back to sleep now?
Blue Exorcist isn't a terrible anime, and it might serve OK for anime newbies. The problem I have with it is, ultimately, everything in it that's good has already been done in anime, and much that's in it has been done better elsewhere. For example, Helsing is a much better demon-fighting action anime. If you want to see an angsty magical boy with adoption angst, who is haunted by his possible connection to the Big Bad, read the Harry Potter series. If you want to see a plucky underdog kid give it all he's got to learn how to do the thing, there's Naruto, Hunter x Hunter, and Pokemon. It also seems similar to My Hero Academia. The point is that Blue Exorcist doesn't stray far enough from the standard shounen formula to be interesting. For a story about such a dangerous profession, they played it extremely safe.