Now, when a cat actually WANTS to come indoors . . .

in my childhood home, there was a side door from the garage
into the kitchen;
when the cats were fed indoors, they were fed in the kitchen.

That wooden door, with a pane of window glass in the top half,
was somewhat the worse for wear:
the cat [s] would leap up to the window pane,
hanging onto the wooden panel with their claws,
and singing at the top of their lungs, to be let in.
Actually the clawing was louder than the singing,
but the cats probably didn't care.