Cuthbert is tired of waking up to Karkat being gone, and this particular time has lasted long enough that Bert is going to take matters into his own hands and find Karkat for himself.

He's immediately drawn to the bioluminescence exhibit because it's one of the more incredible things he'd seen in the Capitol so far. It's unfortunate that he's so mesmerized by it that he doesn't notice anything wrong until he slips on something wet and slick.

Luckily, Bert's reflexes are quick enough that he doesn't fall, but he does tear his eyes away from the glowing everything around him to see what he slipped on. He just barely manages to not yelp at Karkat's lifeless eyes as they stare back at him. It's obviously a fresh kill, or the body would be gone, so Bert glances around quickly and when nothing stands out to him immediately he grabs the severed head and makes a run back to where he left Susannah.