Warning!

In this unique universe, most females are naturally born with a key necklace around their necks. Most males are naturally born with a lock necklace. If a female inserts her key into a male's lock, they, by heart, are soulmates and both lock and key will disappear into thin air.

What happens if a girl finds the biggest rabbit hole she's ever seen before? What happens if she falls through?
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What happens if she finds her soulmate by mistake?