Summary: For the first time in their lives Han couldn't always tell where Leia ended and Luke began. Post-Crucible.
Author's Note: This is wholly self-indulgent crap which exists because Luke&Leia is my favorite thing in any galaxy.
They were starting to unnerve him.
Which wasn't so unusual really. Luke and Leia had been unnerving him since the first day they'd all met, falling effortlessly into sync and finishing each other's sentences as if they could read each other's minds – which, of course, Han learned later was because they actually could. It had only gotten more intense with time and Leia's training, but it had never been anything beyond what Han figured might be normal for Force-sensitive siblings, beyond what he would later see mirrored in his own twins.
But this, this was different somehow, more – and had been ever since they'd gotten back from chasing those Columi brothers through kriffing whoever-knows-where inside that creepy monolith. It was little things mostly – things anyone but Han probably wouldn't even have noticed: Leia had started drinking hot chocolate with nearly every meal, brushing off Han's reminders that she'd never cared for the stuff in the past. Luke meanwhile had taken to standing with his hands clasped behind his back in a pose that had once been so uniquely Leia's it had actually blown her disguise on at least one occasion.
Little things, but after a while they added up to a lot. It was almost as if tiny bits of each of them had gotten mixed up in the other when they'd rematerialized out of the Force. Not that Han had the faintest idea if such a thing were even possible in the first place. He was trying to take it in stride though, as he had all the other crazy Force-based happenings that had come to define his life over the last four decades, and all things considered Han thought he was doing a pretty good job of it.
But then Leia would arch an eyebrow just so or Luke would stamp a foot in frustration, and yes, it was more than a little unnerving, because for the first time in their lives Han realized he couldn't always tell where Leia ended and Luke began.