Kell might have warned him what was going to happen when he took his hand. All Wilhelm can do is watch, wincing and sucking in his breath as Kell slices his hand open. He marks the door with his blood. Closes his hand around Wilhelm's — in shock, he hasn't thought to retract his. An incantation, as immutable as granite. Then—

The world spins around them, or maybe they're spinning, blending into the darkness around them, blurring into nothing. A dense pressure on his chest holds his scream in.

When everything slams still, Wilhelm spills onto the floor. He would have ended up there by merit of his own momentum, but Kell doubly ensures his downfall. Dazed, he heaves onto hands and knees to wretch. Thankfully, what comes out is little more than spit.

"What the fuck?" he demands, wiping his mouth with his sleeve.