千早は泳ぎ始めた。脇に綾の身体を抱えているので不恰好なドルフィンキックしかできず、数メートル進むのもひどく時間がかかる。(苦しくない)(苦しくない)
 どきん、どきん。静かな水中で、自分の心音だけがひどく大きく聞こえる。

Chihaya resumed her strokes. With her whole left arm carrying the weight of Aya's body, crude, jerking butterfly kicks were all Chihaya could afford. Her progress was slow, consuming precious air and time to cover just a few yards.
Thump, thump.
The water was all still, with only Chihaya's own heartbeat pounding in her ears.

DIVING GIRLS ILLUSTRATED 28 SAVING AYA


英文あらすじ(Synopsis):

Chihaya, fighting off her panic, pauses briefly to think. She is trying to remember what Aya had told her earlier - about the rupture in the outer hull and how it led into the cargo bay, several compartments stern of the hatch she just came through. Chihaya looks around, carefully ascertaining that she is headed towards the right direction. Chihaya then kicks off to a start.

And in case she is ever wrong, there is no other way she and Aya can cheat their death.