Icing to the Cake
"Plum~"
"You don't fear water? That's really good to learn. Let's go then."
Splash!!
Alex quickly swam down towards the tunnel but as he was moving, a very thin and transparent film started covering his whole head. It was Plum's doing. Alex was, of course, surprised but he simply waited to see what the Spirit Beast is up to.
After covering Alex's head till his neck, Plum communicated with Alex to release his breath and start respiring like he normally does on the land. When Plum delivered that message, Alex was filled with anticipation.
Alex released his breath like he was told and then he breathed in. Alex did this a few times but he didn't feel any difficulty in his respiration. Just like he had guessed, Plum was filtering oxygen from the water around him using its body's unique composition.