Ok, so, Amada released some scented trading cards in the 90s. Obviously the entire card was not scented, just a part of it (like scratch-and-sniff presumably). Some cards make it easier to see this circle of sniffable area, like this one:

You might recognise the art on them and how each of them featured different flowers, because they were floral scented. So the scented patch goes over what you’re smelling; ie. the plants.

But what

are we smelling

here…