Aqua is a pretty girl wearing a sea-themed ball dress. Despite being a Chess Piece, the happy and rather unpredictable Aqua always keeps a smile on her face, much to the surprise of Team MÄR. Aqua refers to everyone with honorific suffixes in the Japanese version, while in the English dub puts either "Mr." or "Miss" in front of everyone's names, including herself.
Aqua appears in the 3rd round of the 4th Battle.