mischievousness

(noun) an attribute of mischievous children. Synonyms: naughtiness, badness.

(noun) the trait of behaving like an imp. Synonyms: impishness, puckishness, whimsicality.

(noun) reckless or malicious behavior that causes discomfort or annoyance in others. Synonyms: mischief, mischief-making, deviltry, devilry, devilment, rascality, roguery, roguishness, shenanigan.