He was worried about her. Nobody should go that long without sleep. Nobody should deteriorate that quickly. Especially not her.

Natasha Romanoff was dying. Not physically.

He saw the bags under her reddened eyes, the constant stupor in which she walked. Slumped over as if carrying a heavy weight upon her shoulders. She tread lightly on the soft carpet floor. She was hesitant to make a sound. She was hesitant to let anyone know her secret.

Natasha Romanoff was dying.

He didn't push her. Only approached her once. She reacted as he'd guessed. Pushed him away before he could get more than five words out of his mouth. She put her walls up, made her face an unreadable mask. She walked away from him with a snarky comment and fake smile. He pretended to believe her.

He didn't.

He didn't hear her pass his door every night. He didn't hear her walk down to the control room. He didn't hear her constantly scanning the radio systems, the web, the database. He didn't hear the Black Widow searching.

Searching for Bruce Banner.

He watched from afar. Kept his distance. Noticed. Her silence during meals, her tortured eyes.

Natasha Romanoff was not only dying. She was breaking.

He saw the cracks. He saw old scars and new ones. He saw the mangled person this world had spit out before them. He saw the ghosts of people she's slaughtered. They lived in her eyes. He'd never noticed them before.

It was the first time he'd really noticed her. Maybe because her walls were up, but they were crumbling. Maybe because she'd been strong for much too long. Maybe he was using a window instead of mirror.

That window allowed him to see her. To really see her. He saw a chained monster. He saw darkness. He saw beauty and death and blood.

He saw the red smeared upon her. He saw the red in her hair and the red in her ledger, and wondered how she'd managed to hold on for so long.

He didn't know of another red.

He didn't know how to help her.

She was breaking. She was falling. She was hiding.

Natasha Romanoff was dying.