Pheben

The Phebens were a race native to the planet Pheben V. Phebens were tentacled, and possessed three eyes on eyestalks. They were a generally docile people, who had been conquered by the Klingon Empire sometime prior to the mid 24th century. As such, Pheben jeghpu'wI' tended to work at low-level jobs, such as cleaning up after Klingons. 

While generally looked down upon by much of Klingon society, Phebens seemed to be better regarded by those Klingons who more closely and often with them, such as the farmers on Pheben III.