The greatest trial descends upon Mile and her friends!! Reina claims that what the "Crimson Oath" lacks, despite having defeated the Rock Golem, is experience in human combat. Taking her will into account, Mile and her friends decide to take on a merchant's escort request. However, the escort request is merely a facade; the true content of the request is to annihilate the band of thieves that frequently appears along the route. Reina reacts sensitively to the word "thief," but she actually has a dark past related to thieves... Furthermore, during their journey, they will face even more enemies and conspiracies, and as Mile learns the truth about Reina's past and the enemies' objectives, her anger finally reaches its breaking point!!