Bro, just because something is heterosexual doesn't mean it's "painful," and just because Karma took offense at being hit on when he was disguised as a woman doesn't make the game or it's developers "transphobic"--that's a little extreme. This is a free game loosely based on fairy tales that happen to be heterosexual in nature. Don't get me wrong, I enjoy gay/lesbian/bi visual novels too and own more than a few myself, but just because a small-scale game doesn't have gay representation shouldn't make it "painfully heterosexual."
Also, Lucette and Rod aren't related by blood and have only known each other for a year, so it's not like they were raised as siblings. Therefore, I wouldn't count it as "incest" in a way that should squick people out. Will it cause problems in the political world? Yes, absolutely. Is it gross? I'd say no, for the above reasons (not related/no sibling bond). Like, if the "incest" could literally be solved by the parents getting a divorce, then it doesn't really count as incest in my mind ┑(￣Д ￣)┍