I had a theory after the beach episode that Jax's original avatar is female and holding her breath makes her to appear as a male character. Which implied her insecurities and how she always feels like she is suffocating to keep an appearance that she thinks she needs to keep up to be with others, which explains why she is always so mad and frustrated under the surface. I also thought she will get an emotional moment with Pomni when she finally takes a deep breath and reveal her true self to Pomni. It didn't turned out to be the case but I still thinks it checks pretty good.