As stated up there in my comment, Heatran is an ideal counter to Clefable. Standard Clefable sets have nothing to hit it. All you really need to do is keep it relatively healthy and you can stop Clefable easily. I suggest Heatran over other Steel types, and there is two reasons for this. The first is its Fire immunity, as most good Clefable sets run Flamethrower.
Definition. The genitive is the case (or function) of an inflected form of a noun or pronoun showing ownership, measurement, association, or source. Adjective: genitival. The suffix -'s on nouns is a marker of genitive case in English.
THE GENITIVE CASE. 1  The chief use of the genitive case in Latin is to qualify nouns. 2  The word or words which are found in the genitive case DESCRIBE, DEFINE, or CLASSIFY the person or thing which is denoted by the noun which is being qualified.