GPS Daemon. Which is a generic class that does not identify the actual app responsible. All we know for certain is that you didn't spend much time searching before posting, as this question has been asked and answered in existing threads.
If you are unwilling to turn GPS off then a lot of apps are likely to access it and you will have to see if you can restrict or disable them doing so on an app by app basis. Nevertheless, the most likely culprit is Google Now. Google is very aggressive in building profiles on your net activity and some Google apps frequently check whether your GPS is active and /or attempt to discern your current location. Ensure that you do not have the setting to allow apps to poll your position even when GPS /Data is off. And for my money, remove the Google Now's permission to access the net unattended.