this is not a spoiler, maybe I was just too slow to realize at the begin of the show
but as I was watching, all these rituals and stuff seemed known to me, they even utilize chaos magick to summon an angel
and i was still thinking "ohh i know that o;"
till the very end of the first season
when this guy names the locked angel in the tub ; "Who else would try to do such thing?, Magus, Aleister Crowley!"

I was like wooooooooooooooooooooooo o;

the name of the anime its to aru majutsu no index!

oh and he appears in "D gray man" too as aryster krory
but i haven't really seen that anime yet.

the thing is that, i wasn't expecting it!
and you guys should watch the show, it has alot of cute magick moments and fights