If you're up late at night wondering over things too, then click the title and write your wonderings.

I'm in at day, but night away,

So night's when all the other's play.

When moving, sleek and long and curvy;

Still, a ball and just as nervy,

Jump, I thought I heard a me,

A line, no fos or fums, just fe.

'Are you a light?'
'No, but I move just so.'
'Are you a sound?'
'No, but I can make them incessantly.'

Riddle Answer A Cat

Riddle Explanation
but night away, so night's when all the other's play - when the cat's away, (the mice will play).

jump, I thought I saw a me - I thought I saw a pussy cat, or I taw a putty tat, the famous line of the animated bird Tweety when seeing the sly cat Sylvester, from a short Merrie Melodies animation.

a line, no fos or fums, just fe - a feline.