Kaiba Seto and his younger brother had been left with nothing at an orphanage. Gozaburo had wanted to use Kaiba Seto's technology. And they'd been betrayed by the very men who were meant to help them, the Big Five.
Kaiba Seto had many reasons not to believe in trust. It seemed to get him little else but backstabbed.
But it's lack is also the very thing that defeated him in the end, and his beloved Blue-Eyes White Dragon.
So when Yugi, comes forward, trying to convince him to come along with him and his friends to Pegasus' Castle, it all seems absurd.
He's read all about people working together, even knows the value of it for work. But these friends don't just play at it, they truly mean it.
So instead of toy with new philosophies, he goes with what's gotten him this far and plays alone.
It isn't until he's standing atop Pegasus's castle, waiting to challenge Yugi, that he is conflicted.
What if they can find a way together? But Kaiba doesn't know what that would look like, all he's seemed to have known is betrayal. How could Yugi be any different?
So he challenges him, to the very brink.
Standing with his life in the balance, Kaiba can see he has only one shot at defeating Yugi, getting him to forfeit. And in the heat of battle, working with Yugi is far from his mind, even as they insist.
How could they know, the pain of trust?
Only Mokuba he'd ever trusted.
And he needed him back.