In the Goshintou series:
Vol.1 - Zettai Meirei
From Psycho Pandas:
â€¢ Zettai Meirei (Absolute Decree)
A wise, genius chief priest, Kikyou, falls in love with the beautiful heroic spirit of a sword, Kazuto. The story of a forbidden love.
â€¢ Rakuin (Stigma)
"I have corrupted you... Mikoto." The third sword spirit that cleanses evil, Mikoto, understands what it is to love the gentle fourth sword spirit, Shiou. However, Shiou is used by a political opponent's freed assassin...!?
Vol.2 - Ryakudatsusha