I will also note that some people would have religious objections to pieces with demonic names. When Hans was running this site, he would not allow some Shogi variants that included demon pieces. While I don't share his religious beliefs, and I assume Japanese demons are not quite the same thing as Christian demons, I see more of a problem with a game that allows for summoning demons in the more usual western sense. I will also point out that the pieces called Demon and Demoness are more commonly known as Dragon King and Dragon Horse, these being the names they have in Shogi.
I am a Christian but I see no real problem with these names. I do think Dragon King and Dragon Horse are better names, both because they are established and because they are less likely to offend, but if the author wants to stay with Demon and Demoness, I don't personally think that is a sufficient issue to veto publication. It is, after all, a game. (And one of my own inventions would be problematic! I now notice that page doesn't have the introduction where I described the origin of the name and the theme of the game -- an M. C. Escher drawing called Circle Limit IV -- I was working on that game and apparently never finished the rewrite...)
I am a Christian but I see no real problem with these names. I do think Dragon King and Dragon Horse are better names, both because they are established and because they are less likely to offend, but if the author wants to stay with Demon and Demoness, I don't personally think that is a sufficient issue to veto publication. It is, after all, a game. (And one of my own inventions would be problematic! I now notice that page doesn't have the introduction where I described the origin of the name and the theme of the game -- an M. C. Escher drawing called Circle Limit IV -- I was working on that game and apparently never finished the rewrite...)