Sprites are about a foot (30cms) tall and are like the lilies. Their apparent clothing (apparel?) is part of them, like the skin of a fruit or the shell of a nut. But it is just a little more versatile though rarely removed. It grows and replenishes itself as required.
There are two exceptions to the apparent apparel situation.
Tree Sprites, like us, prefer to be dry most of the time.
Watersprites like to be wet and therefore stay in the water most
of the time but occasionally dry off for fun.
Or in Tony's case sit half in and half out
There were giants in the earth in those
days; and also after that, when the sons of God came in unto the daughters
of men, and they bare children to them, the same became mighty men which
were of old, men of renown.
Giants, as Tony the watersprite was aware, were not particularly
strange.
Maybe the passage explains the Giant's squire though.
Perceptive readers will also notice an allusion to Ephesians 6:

The
real secret of the Sprite Stories is, however, that they provide
a wonderful excuse for constructing photo-montages and animated Gifs!
They were revised and extended in August 2001
and somewhat refurbished in October 2002