'Fun' is just a word. Your use of it probably doesn't coincide with the standard meaning. The standard version of fun could likely be easily boxed in an orgasmium type state. You've chosen a reasonable sounding word to encapsulate the mechanisms of your own preference. Nietzsche would call that mechanism instinct, Crowley love. What it boils down to is that we all have a will, and that will is often counter to prior moralities and biological imperatives.

My own arbitrary word for preferable future states is 'interesting'. You'd have to be me for that to really mean anything though.