hunchback    inyōnzo (also refers to the hump itself)
(to be) kurwāra inyōnzo
En-En dictionary 
inyōnzo (iny-)     3  class 3
singular: i-,in-
plural: i-,in-
  
hunch on back, lump, hunchback
umunyanyonzo (aba-)     1  class 1
singular: umu-
plural: aba-
  
hunchback