Tales of Leo Attiel

is a Japanese light novel series written by Tomonori Sugihara, with illustrations by Okaya. The series began publication on June 10, 2015 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
The Principality of Atoll, sandwiched between the Kingdom of Allion in the west, the Federation of St. Ditian in the east, and two great powers. The second prince, Leo Attil, was sent to Allion as a hostage, and was engaged in martial arts and scholarship under the Taishou of the frontier. And the times will reach a turning point. The relationship between Allion and the neutral power Conscon Temple, which is in contact with Atoll, has deteriorated.

Reinforcement Percy from Atoll, Camu the Conscon monk, and Quon, a mercenary from a remote area, work together to counter the looming Allion army. During the battle, the three and Leo meet their destiny.