I would say, on the whole, I'm not really a morning person.
Okay, definitely not a morning person. And as the day rolls on, I realize, well, if I want to include all the hours of the day then I'm probably not a day person either.
Of course, eventually day turns to night. I could say I'm not really a dusk person, just at the time the sun sets. But if I'm honest I should really include the entire night.
So I'm not a night person either.
What's left?
Napping and sleeping.
I'm a napping and sleeping person.