From customer service to Marvel marketing gimmicks, chat bots have come a long way since “SmarterChild” entertained users on AOL Instant Messenger in the early aughts. Now, Microsoft is hoping to steer artificial intelligence into murkier waters—namely, creating bots that mimic real, deceased people.

According to IGN, the tech titan has filed a patent for software “creating a conversational chat bot of a specific person” based on “images, voice data, social media posts, electronic messages, written letters,” and any other so-called “social data.” It wouldn’t be limited to deceased loved ones—you could also create a chat bot for a favorite fictional character, a living friend or celebrity, or even yourself. That said, it seems reasonable to assume that at least some people would want to use the technology to spend time with those no longer with us.

Since Microsoft has yet to create a prototype (that we know of), plenty of details are still up in the air; and the capabilities of each chat bot will likely depend on how much “social data” exists. The patent suggests that some bots will sound like their real-life counterparts or even exist as a 2D or 3D model of that person. They might even be programmed with “a perceived awareness that he/she is, in fact, deceased.” As Forbes points out, this technology could take “protection of privacy” debates to new heights—we don’t know to what extent people would be able to block others from creating chat bots based on their own (or their deceased relatives’) data.

We can really only guess how walking, talking models of our dead loved ones might affect us—and society as a whole—but Black Mirror’s season 2 episode “Be Right Back” offers a little insight. Without spoiling anything, it’s not exactly a happy story.

[h/t IGN]