乖 is primarily used for children and pets. When used for adults, it can sound patronizing or intimate (between couples).
culture
In Chinese parenting, calling a child 乖 is one of the highest everyday praises, meaning they're obedient and easy to manage.
Components
ideograph
乖guāi
well-behaved (originally: contrary)
Graphically a top stroke 丿 over 北 (back-to-back figures) with two extra dots — originally meaning opposite, contrary (people facing away). The modern sense 'obedient' is a complete semantic flip. Treat as an indivisible ideograph; the modern shape resists clean decomposition. Indexed under Kangxi #4 丿 (piě) by stroke pattern.
Filed under radical 丿 (piě, #4) by convention. 丿 is not a separate component in 乖, so no strokes are highlighted.