Cobalt Plus: "No Air Left" Training (Patreon)

Chihaya and Aya engaged in a training they had thought up of to further boost their underwater perseverance... testing how many minutes they can stay under after they exhaled out all air. 

Aya: "...... ...?"

Chi: "..... ..."

(A bit hard to communicate without any bubbling!:-))

Requester: https://www.patreon.com/user/creators?u=2721441