Usagi has never had a high opinion of ninja; they are untrustworthy and dishonest by their very nature. He'd never questioned that, because he had never encountered even a single ninja who challenged that belief.
Until he met Leonardo and his brothers and master.
They were so different from his conception of ninja that he almost wanted to question them, to ask if they were sure they fell into such a category. Never had he seen such loyalty in ninja as he did within that family. Never had he seen such honor in a ninja as he did in Leonardo. Apparently the old adage was true; there are exceptions to every rule.
It was, he supposed, a good reminder that opinions should always be open to revision.