Mischief
Part of speech: noun
Definition: Harm or evil caused by an agent or brought about by a particular cause. One who causes mischief. In a milder sense, one who causes petty annoyances. mischief-maker. Vexatious or annoying conduct.
Example sentence: I love the characters not knowing everything and the reader knowing more than them. There's more mischief in that and more room for seriousness, too.
Mischievousness
Part of speech: noun
Definition: The characteristic of being mischievous; the tendency to make mischief.