漆黒 しっこく
shikkoku

Noun
no-Adjective

1. jet-black; pitch-dark; raven-black; stygian

Formal Register
くろ天使 てんしは、その漆黒 しっこく つばさ おうきく ひろげて、空 そらへと がる。
kuroi tenshiwa sono shikkokuno tsubasao ōkikuhirogete soraeto maiagaru.
The black angel spread those jet-black wings wide and flew up into the sky.