While this could be seen as just a typical villain monologue, it could be hint about the character that’s about to get killed – they could be someone close to the villain, perhaps even a family member. However, the way the two of them speak to each other doesn’t indicate a lot of familiarity at the same time, so it’s hard to tell.
In any case, this is a conversation that has been taken out of context, so many details about it could be interpreted in different ways. Of course, this is one of the best kinds of leaks for dedicated fans of TV shows who love to discuss their favorite production on message boards.
There has already been lots of speculation about the exact meaning of the dialogue that we saw, but until the actual episode airs, there’s no way to know for sure. It looks like the show is going to get a bit more dangerous for the main characters though, with the introduction of a serious villain that could be an actual threat to everyone around him.