Board Thread:False Info and Speculative Discussion/@comment-78.0.215.197-20150202084809/@comment-4091815-20150216201440

It actually works to varying effect on "non humans" as we saw with the Oni and Scott.

How do private homes keep vampires out in Buffy? Something in their make-up won't allow them to cross unless invited to do so.

It's not a spell cast on the vampires or the houses - it's just part of what they are.