Lela is nervous about today's session - Terra is in full control and that is a bit of a roll reversal for the two of them. Lela squirms and whimpers, bound on the exam table, anxious to see what Terra has in store for her. Terra has a series of exercises to put her through, to test her ability to hold her breath. She straps on Lela's blue mask and gets everything into place. They begin with some deep breaths, and some long holds, then together they try a new bubble bottle. It's harder to breathe while pulling air through the water in the bottle - to add to it Lela has to hold her breath again, repeatedly. Finally Terra decides the tests results were satisfactory, she pulls the black tube from Lela's mask and let's her cum