Jesus Gyrsur. I want to see the real version

That's some next level figure there.
you trust the protocol which you verify with your own device which implements BIP 174. the other party signs the tx offline with his device and exchange a SD card with you. you verify the tx offline with your devices and after this you hands over the Cocaine.
I just cant wrap my head around what prevents the hillbilly from spending that input that he used in his offline transaction with me on the block-chain before I can get home and publish the transaction myself.

Really I need to actually read the whole BIP myself and stop being lazy. Was just kinda hoping someone here would have a quick answer that would bail me out of all of that work.

maybe a collision if you upload the tx and he doesn't do that which prevents him to use the
a second time? have to read it too.