Hans and Elsa I couldn’t tell you why its popular aside from hans is hot (sorry, he is) and Elsa isn’t canonically attached.

As for Elsanna– that one is definitely because of how intense and close their relationship is. Their love is the central factor of the movie and they are very emotionally enmeshed. You can read their story in a very ‘lovers reconnecting’ way. Honestly it was what saved the first movie for me, because other than that I didn’t enjoy it much at all ^^;;

Others please chime in!

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