he wouldn't tuck me up

Hi, I was doing some work for a guy who comes from england, and when it came to talk about my payment, he said that I shouldn't worry; that he wouldn't tuck me up. I understand that it meant that he wouldn't cheat me, but what's that got to do with being tucked up??

I suspect he was using it as a euphemism for "fuck you up".

Possibly "Tuck you up" as in putting a child to bed? Make you cozy and comfortable. Though I guess if he takes Victoria's route and severely injures you, then the payment will be the last thing on your mind.