nag

The room is never cleaned, so her mother nags and nags until she explodes with frustration and threatens to sell her to the lowest bidder.

I guess it happens all the time in crime stories where the detective suddenly remembers a bit of conversation that nags him in some way, then for some inexplicable reason, it's just right there in front of you, like a sign pointing 'here!

But at night, around the uncertain edge of dreams, and when the wind nags, there are few whom an odd sound will not thrill