Mystraven

It's an inflation contest with Arc and Mukei dressed in latex swimsuits tailored to show their pouches but hide everything else so only the shapes of their swelling chest and expanding belly's are revealed as their clothes strain to contain each new inch as they balloon one another.

With the air hoses disappearing into their pouches the object of the game is more or less to see who can pop who first. They're both nano-furs so they'll just reform if they go out with a bang, it's more or less a friendly rivalry.