Stiff

凝る

koru

(of muscles, or parts of the body)

固い

katai

(figuratively: of policies and rules and their application and enforcement)

固い

katai

(of a person, formal in behavior, unrelaxed)

堅い

katai

(colloquial: harsh, severe)

硬い

katai

(of an object, rigid, hard to bend, inflexible)

オッサン

ossan

(average person, usually male)

カモ

kamo

(person who is deceived)

無銭飲食

musen-inshoku

(US: person who leaves without paying the bill)

食い逃げ

kui-nige

(US: person who leaves without paying the bill)

払い忘れる

harai-wasureru

(to fail to pay money one owes)