Veteran adventurer Hakura has survived countless trials, but a battle with a deadly hydra nearly ends his life. He is rescued at the last moment by Leen, a curious and unscrupulous young woman with the rare power to tame any monster. Owing her his life, Hakura decides to travel with her, and the two bicker and argue the whole way. What brought this unlikely pair together, and what adventures lie ahead, remain open questions. The fantasy series mixes action, comedy, drama, mystery and romance.