Attack on Titan: Since That Day

Over a century ago, mankind was devoured by giant beings of unknown intelligence and origin known as Titans – creatures that eat humans alive indiscriminately and for no apparent reason. The remaining population has managed to survive the last hundred years only by building a multi-walled city capable of keeping the Titans at bay, training military recruits to patrol the perimeter and gather intelligence about their mysterious foe. Eren and Mikasa have lived a relatively peaceful life behind the city's walls, but when a massive Titan appears, smashing the outer barrier and unleashing a wave of terror, their lives are brutally changed forever...