JP = Japan Post
I tried something similar as a child to send my friend a letter. I wrote their address as the return address and dropped it off at the post office… They sent it to me anyways.
“Neither snow nor rain nor heat nor gloom nor teenage subterfuge…”
Neither snow nor rain, nor gloom of night shall stay these couriers from the swift completion of their appointed rounds
Meanwhile in the US, you couldn’t pay them to return your shit.
I used to use a website where you could send a postcard to a randomly assigned address of another site member on there, and in return you’d get a postcard back from a different random member. One time I wrote the address too close to the stamp area so I could only fit one stamp up there, and had to put the remaining stamp postage at the bottom, and then I dropped it in a mailbox in town somewhere.
Japan Post missed the extra stamps at the bottom and so returned it to my house, despite it being a postcard with no return address to a random country I had no connection to. I lived in the boonies so there weren’t a lot of foreigners in town, but there were definitely at least a few others.