"The Obliviate charm removes the memories entirely, why is the Extractus different? Why does leave an echo instead of removing it entirely? It isn't copying the memory or else it wouldn't be described as an echo, it just would be as normal." Theo remarked, his pale blue eyes sharp and questioning. Harry rolled his eyes before stepping away from Theo before the intelligent and curious boy could think about poking him again. Hermione had moved over to stand next to Theo looking over his notes, their eyes alight with their shared desire for knowledge of Magic.