Will everybody please get it finally right?

Kawaii => Kawaikunai => Kawaikunee

Cute => Un-cute => Un-cute when Ranma mumbles it.

are you sure? My translation has it Kawaiikune...

Kawaii is an i-adjective

To make an i-adjective negative, you do this...

Kawaii -> delete the last 'i'
Kawai  -> add 'kunai'
Kawaikunai -> to do Ranma speak, change 'nai' to 'nee'
Kawaikunee

You can do this with all i-adjectives!

Kun-chan...