For corruption to be proven, the "dui jia guanxi" has to be proven, i.e. the bigshots must be proven to have known that they are giving back something (possibly the contracts or deals) in return for something given to them (possibly the pussy).
If the bigshots thought that the "lovely lady" was merely head over heels in love with them or was hot for their bodies and they were not aware that the deals were being made in return for the roll in the hay, it may not be deemed corruption.
The next question would be whether it would be considered inappropriate behaviour for these bigshots to have a roll in the hay with their chiobu supplier without evidence of "dui jia guanxi" and what would be the punishment for that.