Destiny Unchain Online: Kyuuketsuki Shoujo to Natte, Yagate "Aka no Maou" to Yobareru You ni Narimashita

Kou Mitsuki is a gamer with god-like skills who also goes by the nickname "Headhunting Crim". He participates in a test of a new game device for his father's new game, "Destiny Unchained Online". But the game was filled with bugs at the start and he ends up as a vampire girl. Meeting amazing allies, and taking the game by storm, the story of a top-tier gamer where anything and everything can change....begins!