Formally, this is an example of positive punishment where the addition of a stimulus decreases the likelihood of the target behavior occuring again.
Negative reinforcement refers to subtracting/removing a stimulus to increase the likelihood of a target behavior (think reducing a prison sentence for good behavior).
I just presumed you turn on “shower thoughts” mode after you’ve done a thorough clean.
Though this is similar to what some Japanese households do where they do a thorough wash and shower, removing any dirt and sweat, and soak in a bathtub to relax afterwards.