This page of our guide to Animal Crossing New Horizons describes the brothers who run the shop.
Timmy and Tommy are twin brothers who run a store in New Horizons. They are raccoons and long-time employees of Tom Nook. However, the brothers and Tom are not related. In previous games of the series, there were rumors that Nook had found Tommy and Timmy on the street, adopted and raised them.
Where to find them?
You can meet Timmy and Tommy every day at their store from 8 a.m. to 10 p.m.
What can they do?
You will sell thousands of fish and butterflies to them, but also buy new furniture and saplings. They're the ones who can also spray turnips - more about that here.