I finished Starsight the other day, and the revelation about Doomslug and its species was pretty much what I expected. But at one point, I think when they were just going to Starsight for the first time, something weird happened. Spensa said "By who," and Doomslug responded by saying "Whom!" I took that as an indication that Doomslug could actually speak the language, but it hasn't been followed up on. What does everyone else think? Is it a typo, or something I've missed? Am I making a big deal of nothing? Or is there something else about the slugs? Maybe you really do have to be sentient to be cytonic.