Pairing: (Tony Stark x sister!Reader)
Warnings: Infinity War spoilers, Tony having a panic attack, character death(s) and angst.
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You didn’t regret going with your brother to the strange planet - Titan, you learned it was called - and you didn’t blame him for the bruises dusting your forehead, nor the gash on your arm, nor the way your ankle was bent out at angle it shouldn’t be. No; you were glad to have come with him. If this was to be the last stand for humanity, for existence, your place was with your brother.

Tony had an awful habit, after all, of acting as Atlas, and trying to carry the weight of the world on his shoulders and his shoulders alone. Far be it from you to allow him to continue in that direction when you knew you could lighten his load.

You limped toward him steadily after the mad tyrant Thanos disappeared into the cosmos; about halfway there, Peter was at your side, slipping an arm around you for support as you both made your way toward where Tony sat clutching his side and praying his nanotech was doing its job in saving his life.

You plop down next to Tony and grab one of his hands, leaning your head on his shoulder. You look toward Strange as Tony asks why he would make the trade, and you sense some big secret in the finality of the sorcerer’s words. Tony tenses at those words, so you squeeze his hand a little tighter and just sit there.

A few minutes pass in this fashion, and you can feel Tony growing restless. You turn to look at him and say, “What could we do, Tony? We’re stuck here. The donut ship is destroyed, and the other ships are almost definitely equally destroyed after all that moon-throwing bullshit that evil Barney on steroids just pulled.” you say, as he opens his mouth angrily. “I know. But we’re here, not on Earth, and there’s nothing we can do right now, Y/N.” Tony nods tersely, and relaxes a fraction.

Just as you think you feel the tension bleeding from your brother, the two of you rise to convene with the rest of the group and make a plan. Before anyone can even get a word out, however, Mantis grabs Drax’s arm and says, “Something’s happening.”

You turn to look at her, and watch in horror as she fades away into nothingness. One by one, your compatriots all do the same. It almost seems like it’s over, until suddenly it’s Peter Parker. Peter, who has become one of your favorite people; Peter, who wormed his way into your brother’s hardened heart; Peter, who was good, and kind, and pure. You watch with unshed tears in your eyes as he falls into your brother’s arms, begging Tony to do something, to stop this, to figure a way he can stay. As Peter fades away, Tony collapses to the ground again. You encircle him in your arms, and he clutches at you, shaking with the effort of withholding his tears. You press a kiss to the top of his head, and as you start to whisper that everything will be okay….

Nebula gives him time, and space, for as long as she can; she hears him whispering to himself that it’s “all his fault” and he “should’ve done better” and “protect them,” as he rocks back and forth, rubbing frantically at the glowing thing in his chest. She recognizes the stages of the panic attack, but doesn’t feel like it’s her place to step in or say anything; they don’t know each other, and she knows she’s going to need his help to stop Thanos. So she allows him to sit, and she waits.

Tony doesn’t know how long he sits there in silence, an endless stream of tears pouring noiselessly down his face before Nebula speaks. He barely registers her words beyond recognizing the sorrow in her voice. It matches the sorrow in his heart. He dusts his hands off, and tries not to think of the fact that he’s dusting his sister off; he stands, he puts one foot in front of the other, and nods at Nebula, who understands what he means and leads him toward the Milano. Somehow, they’re going to fix this, and he’s going to get his people back.

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