Age of Terror is a Manga/Manhwa/Manhua in (English/Raw) language, Manhua series, english chapters have been translated and you can read them here.
The Summary is
After a weird hundred years where ghost were appearing, only one-tenth of mankind remained and the number of ghosts exceeding the number of humans remaining! In order to survive, humans needed to choose a “companion ghost” from birth, and constantly cultivate their own companion ghost so that they can be used to fight against other ghosts. The world has entered a weird era of co-existence with ghosts! With the help of the system, the invincible ghost cultivated by Lin Feng causes the whole world to tremble