wrong end of the shaft

Idiom, literally meaning: one the receiving end of someone's penis (in slang shaft) rather than the person who possesses the penis (again shaft). In usage this means someone getting fucked figuratively rather than doing the figurative fucking (in which fucking is the preferred position).

Often used in relation to a business transaction which is one-sided.

While uncommon this idiom can be used in a literal sense and would generally refer to not only the act of being on the receiving side but also of a penetrative act that is disliked or not enjoyable (e.g. anal sex, double penetration..)

Figurative:
"I sold my truck for $2K to some idiot."
"Oh man, that shitbox? He was definitely on the wrong end of the shaft on that one."

Literal:
"James and I DP'd this chick last night.. man, was she on the wrong end of the shaft."

business transaction

Money or services exchanged for services or product.

"How'd the business transaction go last night?"
"Good, I gave her 20 bones and she did a little slob on my knob"