In my market, I was part of a team to first bring character based marketing to the juice box segment. They were fruit characters with a number of occupations, a rock star apple, a soccer playing orange, a video game playing grape. Yes, we could have used a real rock star, a real soccer play, a real video gamer, but we wanted to build a timeless trio. We were also wary of linking our kid based brand to real people with real problems (everyone has problems).
There were some lessons learned from the test markets. The biggest one is that while girls may buy boy or girl characters, boys will only buy boy characters. The woman in me might have riled at how sexist that was but the businesswoman knew in order to maximize profits, we had to launch all male characters.
Why did we decide upon fruit? Well, that was an easy choice. The fruit characters represented the juice flavors. We also lucked out because fruit is a variety of primary colors (kids love primary colors – I don't know why so many parents paint kid bedrooms in pastels).
If you're thinking of creating a character to represent your company, there was a great article in Entrepreneur talking more about it.