Within a walled city that separates our world from the kaiju trying to destroy it, humanity fights for survival in this intense new yuri series. Ever since they were young girls, best friends Yorino and Haruka have been training to join the ranks of the Bulwarks-soldiers who defend humanity from the kaiju trying to break through. But when Haruka is killed during a routine drill, Yorino's world is shattered. Will she ever be able to open her heart to another? Strap in for intense, apocalyptic romance!