Someone else answered but its short for "hardworking careerwoman", baribari meaning energetically or vigorously (i think derived from the sfx of crunching or grinding), career from english, and the working and woman parts being dropped from the abbreviation.
Rihito has the self control of Bodhisattva cause if there was a mid-30s career shortstack woofing at me like a dog I'll slather peanut butter on my nutter and turn her into my meat cleaner cuh gotDAMN