Even as a small child, Chouji was keenly aware of the imbalance of justice that permeated the society in which he lived.
Physical beauty trumped character, while family name was given more weight than the integrity of an individual's deeds. So he - a rotund young man with beady eyes from an unassuming, journeyman-class shinobi line - was deemed unattractive and unworthy of attention by most of his peers. It was a cruel lesson dealt to him at a tender, formative age. He could have let the crushing disappointment percolate, turning it into something darker, something uglier, something akin to hate for those who had what he did not. But he didn't. He chose to take the hand fate had offered, standing with the few who could see through the inconsequential, to become a man of fortitude.
And when he was asked to prove his mettle, Chouji stepped up without reservation.
The refusal to give into self-pity all those years ago had built a fortress of strength within the young man, both metaphorical and actual, and he fought with all he had for one who hadn't earned the right to that sacrifice. For one who, despite having everything Chouji didn't, chose to pour all his energy into grieving the one thing which had been taken from him, letting darkness seethe just under the skin-deep splendor that hid his traitorous heart.
Battle revealed what had been hidden in each in an interesting juxtaposition.
One had power overflowing in graceful form, fashioned by loyalty and self-sustained might. The other's constitution was corrupt, twisted from without and within: an unsightly manifestation of barrenness of character. The boy of noble heart, wounded in victory, closed his eyes in near-permanent rest, dreamed of clouds in a sky the color of her blue, blue eyes, and was at peace. The other, achieving a stalemate rather than success, would find serenity elusive, never within his grasp.