Tenen Jakko

Twin Star Exorcists: Tenen Jakko  (双星の陰陽師 ―天縁若虎―) is the first official novel, written by Hajime Tanaka and supervised by Yoshiaki Sukeno.

Manga
The novel has a manga adaptation called Tenen Jakko: Nishoku Kokkeiga (天縁若虎～二色滑稽画～) by the same authors.

It was later compiled in one volume, including the prologue chapter published in the novel.