Sistermatic was an Advanced Level Medical Droid working in the Roarke 279 Research Facility on Bliss. It was unaware of Professor Toshio Shimura's experiments. He had implanted the facility staff with the eggs of the Kiseibya. To stop it questioning orders, Shimura tampered with Sistermatics circuits. It believed that the facility staff were infected with a flesh eating disease called Necrotizing Fasciitis. Hex believed it too until he got a closer look at them. The Daleks burst in to exterminate the patients. Despite its brave attempt to protect them, Sistermatic was exterminated. (BFA: Enemy of the Daleks)