>>110796740Jack is genuinely stupid when it comes to socializing with the opposite sex. He might also be colorblind.
Aku is good at pretending, to a fault. Most people can point out his disguises from a mile away. Even Jack eventually started catching on, at least by season 3.
If the character knows who Aku is beforehand, and knows in advance that he can shapeshift, he probably couldn't get away with it.
Of course, he could take a disguise for a first meeting, but he prefers to meet new people in his normal form. The Imakandi intro comes to mind.
