英文あらすじ（Synopsis）：

Several minutes' rest inside the air pocket givesChihaya a renewed strength. Perched atop the bunk bed, she thinks of an aquarium - but it was her, not the fish, who was in the tank and observed by inhabitants of the sea.

It comes to Chihaya's mind that she had lost her goggles in the mess hall. Aya volunteers to retrieve them, quickly taking a deep breath and plunging back into the dark water.After two minutes have passed, Chihaya becomes worried; yes, Aya is a supergirl, but it just might so happen that she is drowning somewhere. Chihaya thought she should go call for help, but wondered if that might be too late.

「苦しいの。無理しないで」手で、ガラスの表面をぺたぺたと叩く。「あたしのことはいいから、早く海の上に出て」
　すると、綾は今度は鼻をつまむとのけぞるように後ろに回転し、また上下逆さまになった。顔にはまた笑みが戻り、何だか悪戯が成功した時のような、得意げな表情をしている。どうやら、さっきの苦悶は演技だったらしい。
　「綾ちゃん」声を掛ける千早に向かって綾は指を丸めてOKサインをすると、両脚をゆっくりと打ち、また滑るように海底へと潜っていった。
　「もう、知らない」千早は少し怒っていた。あの人魚姫は、もしかすると心配する必要なんか全然ないのかも知れない。

"You - you're pushing yourself too far, " Chihaya exclaimed, striking the glass surface with the palm of her hand. "Aya, don't worry about me. Go. Swim up and take a breath, pleease.".
Then Aya pinched her nose and flipped her body backward, eventually standing on her head. Her impish smile was back, triumphant that her trick had played out well. Chihaya now realized that Aya was just pretending to be out of breath and suffocating.
"A-Aya?"
Noticing the movement of Chihaya's lips, Aya winked, stroke her legs gracefully a few times, and glided down into the depths of the sea.
Chihaya was baffled. Maybe there was no need to worry about that mermaid of a girl. She could hold her breath forever.