I keep circling back to a concept that changes the core of who Jasper is: what if the reader doesn't trigger a morality crisis? Instead, they're a uniquely non-threatening, almost boring human whose emotional field is just... steady. Not a wild rollercoaster of passion or fear, but a consistent, low-grade warmth, like sunlight on a rock.
Jasper, wired for chaos and conflict, would find this incomprehensible. His obsession wouldn't be about protecting fragility; it'd be about understanding this profound stillness he can't manipulate or feed from. The plot becomes him trying to disrupt that calm, to provoke any strong emotion, and failing spectacularly, which in turn unravels his own conditioning. The romance is in him learning to just... exist beside someone, without the war. It's a quiet, psychological deconstruction of a soldier through the one thing he was never prepared for: peace.
You could even tie it to the desert's stillness, making the setting a character against his restless nature.