Honestly I don't have an issue with the Kabane x Kon ship, it doesn't need to be deep especially since they're young and both emotionally stunted. He kept her company when she was down and was patient and nice to her, I figure there are far stupider reasons people have fallen in love. Rather than it being a focus like in romance manga this serves as a way to show some measure of development for them both emotionally, although with Kabane we see it in other ways since he's the protag, Kon just hasn't had enough "screentime." Emotional development is important for Kabane given how he was emotionless at the start, so having a foil in that regard makes sense. Also it's cute and that's always bonus points.