Boshar

Boshar was Doctor Antaak's pet targ in 2154. Boshar lived in Qu'Vat colony, where the targ was allowed to roam freely. Antaak once stated that he would never keep Boshar locked up. The Klingon doctor also revealed that Boshar had been his first patient when, as a child, he had stitched up the targ's side when Boshar had split it open. 

After Antaak lost his cranial ridges as a result of the Klingon augment virus, he doubted even Boshar would recognize him. 

Boshar