My dad always likes to tell us about the Christmas when my uncle bought my aunt a tin opener (a good one!) for Christmas, she was apparently rather unimpressed but the story has given years worth of good laughs.
I also remember when my dad bought a holiday in New York for my mum and himself for Christmas, but the tickets were in a small envelope right at the bottom of a HUGE box filled with packing peanuts.
What terrible/joke presents can you think of that would be a good laugh on Christmas day?
My sister once put some dog doo in a paper towel tube and wrapped it as a present.
But somehow I don’t think that the kind of prank you’re looking for.
It does make for a funny story, but yh, probably wouldn’t give it to the GF!