Author's Note: First foray at all into this corner of MCU fandom, but I got hit in the feels, okay?

The First Law of Thermodynamics

Fitz had done the math. He knew what was going to happen and who was going to get the oxygen. With his arm in a sling, taking the breath himself would kill them both.

But not Jemma. She was the better swimmer. She was stronger. She was beautiful. She was— She was going to make it, he told himself breathlessly. She was going to live.

"What do you think it's like?" she had asked.

I want my energy to go to you, he thought, glancing up and catching her adrenaline-induced smile. If there was any sort of God in the universe, if they really would go on to give others life, he wanted to give her life.

"A good one, I hope," she had said.

Whatever Jemma had given new life, Fitz knew it was a good one.