U-Marika Kato, umfundi owenza unyaka wesithathu e-Hakuoh Girls' Academy, uyisigelekeqe esisemthethweni sasemkhathini esine-Letter of Marque. Phakathi kwezifundo zakhe, ukuhola ikilabhu yesikole seyacht yasemkhathini, esebenza isikhathi esithile eCafe Lamp, kanye nokuba ukapteni womkhumbi wezigelekeqe zasemkhathini i-Bentenmaru, izinsuku zikaMarika zimatasa kakhulu. Ngolunye usuku, uMarika uthola umsebenzi wokugebenga umkhumbi wabagibeli bezinga eliphezulu, futhi uthola ukuthi ohlwini lwabagibeli kukhona uKanata Mugen, umfana “ophethe umthala”. Ngakho, i-adventure ehlanganisa umjaho we-hyperspace phakathi kwezigebengu nomfana oyedwa uyaqala.
