A chronologically impossible scenario, such as a character meeting their older or younger self, or two characters from different time periods meeting, even if one of them should be dead or shouldn't be born yet.

For example: [[Asahina Mikuru]] meeting [[Asahina Mikuru (adult)|adult Mikuru]], [[Revolver Ocelot]] meeting Major Ocelot, or [[Altair Ibn la-Ahad|Altair]] meeting [[Desmond Miles]].

h4. See also

* [[age comparison]]
* [[alternate universe]]
* [[anachronism]]
* [[Doraemon Darake]]
* [[dual persona]]
* [[time travel]]
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