Yoo Sung Woo is a Manga/Manhwa/Manhua in (English/Raw) language, MONSTERS series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

The story of the 'shadows' who are born with special abilities on the night when the black star arises. [Pls do edit if there is any details wrong]