Zain had been holding her breath for a very long time now. The tank was filled to the rim with water. She was kicking hard, swimming from side to side to get air, but there was no more air there. She knew that she couldn't hold her breath much longer, and she might start drowning anytime soon. There was nothing else she could do. She just stayed by the window, staring at Sebastian with what looked like a goodbye stare.
Sebastian was by the window. He was looking through to be sure that she was okay before he went back to the puzzle. Now he was wondering why she no longer looked like she was in a panic. She was peaceful. Sebastian saw this as something awkward. She just stood there, with her arms on the window, as bubbles continued to escape her mouth.