Bruce really disliked dealing with Brother Blood. It wasn't that he couldn't acknowledge the supernatural - he knew 'magic' existed, in some form, he'd seen it; heck, he was kind of friends with Zatana. Magic was real, or at least 'science we don't understand yet' - however he had to label it to make it alright in his head. And it wasn't like he was scared of dealing with it - he was the Dark Knight. Not much scared him. Magic did not scare him.
Magic was just... messy. That's what it was. It was messy. So at least it usually kept itself out of Gotham.
But today was not 'usually', and thus Bruce was picking what was left behind after he'd busted one of the cultists' hideouts. It wasn't a pleasant thing to investigate. A lot of candles. Old parchment. Runes scrawled everywhere in what he hoped was only - but knew probably was not only - red paint. An uncomfortable amount of 'red' was involved here, really. There was an aesthetic here and he was not a fan.
One of the cultists had been shouting, as they were arrested, some mix of Latin and English about some demon lord they probably worshipped. So identifying what he was pretty certain was some crude summoning circle just put him more on-edge. He wanted to finish this investigation, figure out what the cultists had been up to, and get out of here and get on with his night.
The last thing he expected was to open a trapdoor and find a living being, bound up like a hostage, chained to a wall. ...Maybe he should have expected that from a trapdoor in a cult den, but here they were. He was immediately on-guard, cautious, uncertain - but he couldn't help but notice the figure seemed... small. And scared. And it was obviously more 'captive' than anything else, wasn't it?
He takes a cautious step onto the stairs down into the alcove, trying to get a better view of you. "Hello? Can you speak?"