Machiavellianism
When someone tries to rip you off fast and mean to get ahead, no matter how much trouble they cause.
Your neighbor said he'd give you his old phone if you helped him move, but it was broken and had no battery.
Your cousin said she'd let you borrow her bike, but then rode off with your skateboard.
Your mom said you could skip chores if you finished your math, but then added more homework.
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