If it wasn't the little house, then it had to be the basement then. Right? Or maybe there was another explanation about the strange things happening here. One that Brook was more familiar with. "Hmm, Usopp-san? Do you think, ah, maybe the one in charge here might have a Devil Fruit ability?" he questioned, watching the stacking of the cards. "That is... well, you've not been to where you met me from, yes? So you wouldn't know, but Mor- the one who was in charge of that place could make zombies with his ability!"

Zombies from shadows didn't seem to be the case here, since everyone seemed to have their shadows during the day, but people did disappear sometimes. Was it possible that they'd gotten their shadows taken and then were being held captive in the basement while the zombie/monster/whatever was out and about at night? They couldn't have been forced into the sun since that would have meant death for the zombie too (could they die?), so maybe...

"Yohoho. This place seems just so similar to back then."