drawing a hole.(Optical illusion)

Good evening friends of this community.

Today drawing a hole through lines that give the perspective of a certain depth. I started with a square with a lot of shadow and then I made other lines to fill in one in the middle with charcoal, until I finished and shading to define the part where the light comes from.

Procedure. . .

To give it a bit of reality, draw a kitten that from various angles looks like climbing, at another angle like observing.

I hope that from your optical illusion you like this content.

Goodbye and thanks for your great support.