I love so much of this manga; the story, the art, the Schadenfreude... but this McGuffin Cube is just showing the absolute lamest motivation; most lame-tastic; lamest fuckery, most foul; Lamestown Massacre.
more like having an affair (which he must take responsibility for else Ruby will be unable to get a mate as she be seen as a lose dragon that would let anyone ride her)and right in front of his recently engage finance who knows what it means to ride a unmated dragon and only put up with it as this was an emergency (Hal doesn't even know what it means to ride a dragon)
She didn't put up with it because this was an emergency, she clearly wants this scenario to play out, it means more power to them, she doesn't really care about monogamy