For feelings angsty: Shiro accidently hurting Galra!Keith when he originally come out because of his PTSD nightmares.
When it came down to it Keith trusted the squad and telling him in them of his heritage was inevitable. It didn't make it any easier though. The fact the entire thing happened as an accident didn't help either. He had, in fact, been coming out of the shower and wasn't quick enough in reactivate the hologram that hid the fangs and claws, the splotchy skin and cat like ears. As a result Pidge caught a full view of his Galra heritage.
Pidge was thankfully accepting and also urged Keith to tell the others. Reluctantly he agrees, however only on his own terms and the green paladin agrees. Its three days later before he calls the others for an unofficial meeting, careful that both Allura and Coran are busy at the time. He doesn't want to force this on them if it wasn't necessary.
When everyone arrives for the meeting the room is quiet and anxiety churns in Keith's gut as he faces them. Pidge sends him what's supposed to be a reassuring thumbs up and Keith gulps before quickly deactivating his hologram wrapping his arms around himself in a pusdo-hug.
"I hope this doesn't… you know… change anything." He's quiet as he speaks, not meeting anyone's eyes. There's a certain amount of nervousness and defensiveness that comes off of him. "It's still me. I'm just as knew to this as all of you. I just though all of you should know."
Hunk and Lance are the first to react, both calm with this revelation. "Don't worry Keith, we know it's still you. You're still our friend," Hank says laying a hand on Keith's shoulder in an encouraging movement and Keith relaxes a bit.
"Yeah. Don't worry, buddy. I don't like you any less nor do I dislike you any more," Lance says clapping a hand on his back. Now Shiro is the only one and Keith turns to him, hesitating.
He turns to the black paladin, "Shiro are you alright with this?" There's no reaction from him and Keith turns to face him fully. "Shiro?" His voice is louder and more concerned as he reaches out to him.
"Shiro? Are you okay?"
Keith doesn't know, he can't, that Sandak has taken his place in Shiro's view. That the purple skin reminds him of a place he'd rather forget, that voice sounds familiar just not like Keith. No, Keith can't know that. Instead he knows the feeling of Shiro back-handing him, of metal against skin. He falls backwards, an ache in his back adds to the pain as blood dribbles from his knows.
"Keith! Your nose if bleeding!"
It's Hank's voice which pulls him from his daze and he sits up only to watch Lance spin around to face Shiro eyes accusing. "Shiro!"
Shiro's eyes have cleared, now he can see Keith. Keith who's laying on the floor with blood dripping down his face and a spark of fear in his eyes and Shiro is reminded he put both there.
He reaches out. "'Keith I am so, so sorry." The words fall from his lips without even a thought.
"I thought you didn't want me to touch you?" Keith's voice is fierce even as he flinches away from the out reaching hand. The same one to hit him.
Keith had always known it would he hardest for Shiro to accept him, but this wasn't within the realm of what he has been expecting. The cold shoulder, ignoring him maybe even something passive aggressive. Nothing like this. A part of him knows the squad will never form Voltron again, that they'll fail their mission to save the universe. Another part of him is too concerned that everything has changed for him to care.