The dragon's harem - Chapter 1365: Quest: Drakaina Hunt

Traversing to a parallel World, Shinji Kamihara discovers a mysterious notebook called the 'Chronicles Of Urban Legends'.By writing urban legends in its pages, he can bring them to life in the real world. In this Japan, many of the urban legends from his previous life are absent—Hanako-san of the Restroom, Hell Girl, Sadako’s videotape, the Eight-Foot Woman, Mary’s phone call, the Seiryūji Tunnel, the Gaze from the Cracks, Tengu Elementary…“Let me unleash a pandemonium of Monsters and Ghosts upon this World!”

I exist in the darkness, disappear under the bright light, and will eventually devour the sun and turn into the shadow of all things… Known by people as the indescribable terror of darkness; the king of shadows; the dark day; the existence of the shadow of the world , is still just a somewhat special high school student, facing a weird death game…

- Description from novelbuddy

The Special Investigations Unit is a covert organisation that no-one in the city knows about, dedicated to investigating bizarre occurrences beyond the comprehension of the living. The Chief Zhao Yunlan isn’t a simple guy either, being the inheritor of the Guardian Order, he has always been a righteous conformist, excelling between realms of the living and the dead. While investigating a school suicide case, Zhao is attracted to the calm and reserved Professor Shen Wei, but the Professor seems to be rather fickle towards him…

- Description from Novelupdates