Growing up as an assassin, the color red only meant one thing to Natasha. Her past.
   The Red Room. She hates her past. They played her, manipulated her into something with one mission: kill.
     The color red also means blood. Whether it is blood spilt by her own hands or blood from those injured during battles. She acts tough but inside it breaks her. The children being sent to orphanages never to see their family again.
   She remembers her last encounter with her family. It was the morning of the day she would be sent to the Red Room.

Natasha: Just admit it mother! You don't love me! You were waiting for my birth to send me away! You never wanted me!

Father: Natalia Arvelo Romanoff you will respect your mother and you will oblige by our rules. You can run but they will take you. They want you. In fact they are here now. You aren't coming home.

Two ladies barge in with the Red Room symbol.  Her father nods at them. One grabs the pile of baggage and loads it into a truck. The other attempts to grab a protesting Natasha. She is refusing. The lady pins her down. Natasha gives her parents cold stares. "I hate you." Then, a needle is plunged inside her neck knocks her out.

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During civil war...
    The famous red hair is in Russia sent by Fury. No specific coordinates. Seems like time off. But why this town.
    Where it all started. She used to come to this bakery all the time before her parents sent her away. She slowly walked along the streets. Memories flooding her mind that she wanted to forget. To erase. Not all of them are bad. She wishes she could forget. But she can't. This is who she is.
•
     She has moved on. She lives at Avengers Tower and has a nephew. She protects him with her life. God help the poor soul that hurts Peter.

     "Aunt Tasha!" The red hair turns in the direction of an incoming small boy. She smiles. "Yes Peter?" He smiled toothily. He is missing his two front teeth. The tooth fairy gave him twenty dollars.
    He hands her a piece of paper. In the center is a big red heart. On the top says, "I LOVE YOU AUNT TASHA, LOVE PETER". "Do you like it? I used it red because it's the color of your hair. It matches you." Natasha smiles, her heart warming up. She hugs Peter. "I love it Peter! Thank you so much!"
   Seeing his happy aunt makes Peter smile even more. "Yay!"
   Natasha thinks. Before the color red was a bad thing to her. But now, she loves the color red. Her past no matter how ashamed she is shaped her into what she is. Her past saved the world. The color red is now her strength.
   After all, when you are fighting, you are fighting to save blood. To save people. Natasha smiles knowing that all the red in her ledger is wiped out. Permantly.