Well now the challenge was favorite anime I've watch so far and I've brought it down to 2 and couldn't decide so let me know you're opinions about my opinions.
I'll start with Noragami. It's one of the most beautifully drawn animes I've seen so far. Yato is a down and out god of calamity that's been traveling the world for thousands of years with no shrine and no followers, with big dreams of being famous one day. He does any job for 5 yen and never has an unsatisfied customer, but for some reason can't be remembered by any of them, until he meets Hiyori Iki. To learn the rest of the story filled with God's battles, mythology, and the occasional wisdom bombs that only a god could drop I would definitely recommend watching it!
Secondly but definitely just as good tokyo ghoul. Kaneki is just a normal boy until he goes on a date with a beautiful girl that ends in tragedy. In order to save his life a doctor must transplant organs into him unbeknownst to him those organs belonged to a ghoul now kaneki must learn to survive as a ghoul because of the rapid transformation his body underwent. Although the story is significantly darker in my opinion it's another must see.