Dust, or a fly.
The fat man with the grey hair and beard that flys to your house in a reindeer driven sleight, cums down the chimney on Xmas eve, slips you a present or five, creeps around the house eating biccys, drinking milk and then flys off again.
House flys
small
get a swat and kill them. Simple.
Very small.
a flies habitat is in house or in poo
They eat aphids, small flys etc.
mostly flys and other small insects.
Flys adapt by living and having sex
they live up to 3.5 days.
Loads of flys might be the effect of another problem. Try checking for bats. If they set up and are pooping the flys might be attacted.
flys