Q. What's pink and fluffy
A. Pink fluff
Q. What's blue and fluffy
A. Pink fluff holding it's breath
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Fluff is loose fibres which collect on your pullover, pants, sofa, etc. Fluffy is an adjective used to describe a soft piece of clothing, or a soft animal. (a fluffy pullover, a fluffy rabbit)
In English, we say that people turn blue if they hold their breath too long.
Now do you get this silly joke??