A person who always interrupts your story with a better story of his/her own.
The number of cats can increase depending on how 'full of themself' the person is. ie (Karen is an 84 cats/Karen has 84 cats)
Someone who always trumps your story and is always better.
Not to be confused with someone who actually owns cats.
Michelle - I went on a beach holiday........
Katrina - My sister's friend's aunty's cousin went to the beach the other day.
Michelle (thinking) - OMG, Katrina is such a three cats.
2. Karen doesn't have 3 cats, she has 84 cats!