Tortoiseshell cats, like calicos, are almost always female, and rare male "Torties" are almost always sterile. The reasons for these anomalies stem from a complicated genetic patterning of chromosomes and genes. If you're interesting in exploring color patterns in cats more fully, learn more with these resources.
Torties also share a common personality trait, so unique to tri-colored cats that it's called "tortitude." Pat, a tortie fan (and personal slave) describes it beautifully, as "an "over the top" personality: impish, playful, loving, humorous, naughty at times, too clever, and totally delightful."
Let's take a stroll through this rainbow of colorful tortie beauties, each one reminiscent of a pile of maple leaves glowing in the crisp fall air.