Ep. 4: Akari delivers a mysterious letter to an abandoned terraforming base in the Adriatic.

President Aria guides Akari to a square where a girl with a belled collar entrusts her with a letter. Mr. Mailman identifies the contents as an outdated video card format and locates the destination: an abandoned terraforming base in the Adriatic. During gondola practice, Aria leads Akari to an unfamiliar canal, where the girl explains the message can transcend time and space before entering a house as Ami. Woody, a sylph deliveryman, flies Akari to the base on his sky-cycle. They discover only a cemetery remains above water. Akari finds the recipient's gravestone and plays the video, revealing a woman named Ami writing to her husband working on Mars, now called Aqua. Akari recognizes the background from her second meeting with Ami.

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