07-09-11
Being in Route has had the effect of softening Mamoru's attitudes and mannerisms. Although returning to his family remains his highest priority, the fact his grandfather is not actively there with him not only removes Mamoru from the man's callous influence and direction, it makes this responsibility more abstract than it otherwise would be. There is no Takatori family or fortune TO protect in Route short of preserving his life. There is also no Kritiker to run, and no world of dark beasts to hunt and destroy.
In addition, Mamoru has been reunited with all of his old friends and the positive influence they exert over him. His Togepi has given him something to take care of instead of a harsh, calculating grandfather. Shiro's childlike nature and cuteness is more endearing to him than he'd like to admit. And all the while, his Togepi has been taking the happiness he absorbs from his surroundings and instilling it in Mamoru's heart without Mamoru ever being consciously aware of the fact.
As a result of this combination of factors, Mamoru has become increasingly flexible in how much his heart and true nature show outwardly. He smiles more easily and more genuinely. He shows more compassion, generosity, sincerity, and loyalty. His sense of morals is less narcissistic. He remains quieter and less easily stirred into an emotional fit, as well as more cautious and pragmatic. He is slowly becoming more social, but retains a sense of avoiding more intimate relationships.
It would be a lie to say he has become Omi once more, but not such a stretch to say that it's now more evident he never really lost the qualities that made his former self so likeable. What he's lost is his reason to hide them.