For the briefest of moments, he looked wrong-footed, brow creased with confusion, until he finally caught on to what Warsman was saying. Oh. Well then.

"Ah, I'd completely forgotten that..." Robin trailed off with an apologetic shake of the head. Really, now, and he was supposed to have graduated amongst some of the brightest minds in England all of those years ago. "English really is a devil of a language to navigate, isn't it? Do excuse me. A folly is a type of building- they're designed to look as though they have a purpose when, in actual fact, they're purely ornamental."

You didn't get many of those in London. Anyone trying to erect a miniature castle, assuming that they even found the space of it, would find it almost immediately populated by any number of wanderers and vagabonds. So much for 'purely ornamental'.