Aquarium.

Aquarium is a summer love story about Aqua, a new maid with a secret, and her young master, an heir to the Francois family who has lost part of his memory. The young master has the same nightmare every night: he meets a girl, they quarrel, and they part with the words “I hate you” ringing in his ears.

One summer, his elder sister asks him to develop his leadership skills in preparation for inheriting the family estate. She wants him to guide and help a new maid grow. Aqua introduces herself as responsible for his well-being, and the young master is soon drawn to her despite her clumsiness and the secret she cannot reveal.

Their different social standing stands between them as they face challenges and opposition from society. The story follows the two as they confront the mystery of the girl in the young master’s dreams and the shadow looming over their relationship.