The first time she sees him, it's late. Clint is sleeping, his head cradled in her lap. Her hand cards through his hair gently while she watches the film. They're alone in the room, the television is muted, and she hears a sigh.
When she looks up, there he is. Agent Phil Coulson. Impeccably dressed in the suit he died in, face calm. Blood drips from the wound on his chest, the wound that killed him, and Natasha knows it's not real. Yet, real or not, she is unable to look away. Unable to drag her eyes from his face, the way he stares so fondly at them.
"Take care of him, Natasha," he tells her, voice echoing through the room. It's just a ghost, just a memory. Just words from days behind them, and yet those words tear holes in her chest. Leave her heart bleeding, begging for him to stay. To just be real. "Please. For me. Take care of him."
Her head drops, eyes falling away from him. Tears fall from her cheeks and splash onto Clint's. Immediately, he's awake, on edge, and staring at her. "Tasha?"
When she doesn't respond, when he realises she can't respond, he wraps her into a hug. They sit there, frozen like that, for what must surely be a lifetime. The same loss, yet so very different, echoes through them.
And over Clint's shoulder, behind his back, Phil is there, standing guard.
The second time, they're returning from a mission. Clint and Tony are with her, all of them blood, all of them exhausted. Stark and Clint fall onto the couches, and Natasha glances at the doorway. There he is. Where neither of the other two can see him, where she alone can watch him.
Part of her wants to scream. To shout and throw things until he comes back to them. Her legs shudder, and she runs to her room. The door against her back, locked, she slides to the ground. It comes out in a torrent, an ocean of tears, and she cries until every last drop has run out.
"I'm sorry," he says, voice echoing through empty space. "I'm sorry, Natasha."
"You're not real!" she cries, no longer caring who hears or comes running. In her hand is a prototype Stark weapon, and the trigger dips under pressure. Then she's staring at a hole in the wall. Staring at Stark and Clint and no Phil in sight.
They're both looking for signs of a threat, one that doesn't exist, and finding nothing. She's going mad. All those years, all that red piling up, and this is what finally sends her over the edge. The death of one man, one man who'd offered them the family they'd never known.
The last time she sees him, there's a gun pointed at her. And there he is, like a reaper beckoning her to the gates of hell. The only proof she needs, to know that this is truly the end. The man on the other end of the gun shouts and shouts, but Natasha doesn't listen. Let it end. Just let it be over.
Walls break down. The Avengers are there, there to save them. An unconscious Banner is taken away by Tony. Clint struggles with the ties around Natasha's wrists, and all she can do is vacantly watch the ghost of Phil Coulson.
Then she looks away, and there is Thor, staring at her and at Phil with the most pained expression of understanding she thinks she'll ever see. The asgardian lifts her into strong arms and says, just to her, "I am sorry, Lady Natasha."
"You see him," she whispers, brokenly, and when he nods all she can do is cry.
"Loki's magic killed him. Now it plays upon his spirit. This is a trick Loki's magic plays upon you. Let it trouble you no longer, Lady Natasha, I will finish this."
Exhaustion comes over her as though a blanket, and her eyes close. Lips press to her forehead, and his voice is there, comforting, saying, "Goodbye, Natasha."