Many Otaku Slang exist in Japanese.
Probably, the most often used one is “神(Kami)”.
“神(Kami)” means “God” and is of course a sacred word.
But in Japanese youth culture, 神(Kami)” is used as “Awesome!”.
“Kami” is often used as an adjective.
“神アニメ（Kami Anime）” =excellent Anime
“神回（Kami Kai）” =impressive episode
“神曲（Kami Kyoku）” =impressive music
曲(Kyoku)=music or song
“神展開（Kami Tenkai）”=exciting development of story
展開(Tenkai)=development of story
“神対応（Kami Taiou）”= generous reception
Incidentally, antonym of “神対応(Kami Taiou)” is “塩対応（Shio Taiou）”.
“塩対応(Shio Taiou)”=dry reception
塩(Shio) means salt. Salt=dry?
Originally, 塩(Shio) is used as slang in Sumo.
Sumo wrestler who lose always is smeared with salt.(Sumo wrestler throw the salt before the match.)
So shio(salt) means boring and other negative things.
Its origin is unknown.
Long time ago, “神技 / 神業（Kami Waza）” “神がかり（Kami Gakari）”were used in good performance of sports, traditional arts and other excellent techniques as a correct Japanese word.
(Waza=technique, skill, etc / Gakari=possessed by god)
As Otaku Slang, it has born and spread mainly from 2ch and niconico about last 10 years.
And as many not Otaku Japanese(mainly teenagers) have get closer to Otaku Culture, this slang is very often used in daily life.
（This application is useful! So Kami!）
(I got a good score on the exam because of your good teaching.How Kami you are!)
In this way “神(Kami)”is a slang that is very positive and useful.
It will helpful when you communicate with Japanese Otaku and ask for Otaku information.
But it is just a slang.
Some elderly person may give you a piece of advice.
“You are too praise. It reduce value of Kami.”
Using Otaku slang with felicity will provide you finer Otaku life.