Day 1 art of the 'Josu Challenge'.
Tail Guard: a cleaving guard with the longsword held by the side of the weilder. This stance leaves the user more open than the rest, however the lack of parrying capabilities are offset with allowing extremely good mobility both on ground and in the air. Its sideways and upwards cleaves coming out from this guard can also pack a punch.
Because of its simplicity, it's Bonnie's main stance.