whimsicality

nouns

the trait of acting unpredictably and more from whim or caprice than from reason or judgment
"I despair at the flightiness and whimsicality of my memory"
arbitrariness, capriciousness, flightiness, whimsey, whimsicality, whimsy
is derived from
whimsical
the trait of behaving like an imp
impishness, mischievousness, puckishness, whimsicality