Shuumatsu Nani Shitemasu ka? Isogashii desu ka? Sukutte Moratte Ii desu ka?  

Do you have what THE END? Are you busy? Shall you save xxx?, 終末なにしてますか？忙しいですか？救ってもらっていいですか？

Five centuries have elapsed since humans vanished due to the terrifying and enigmatic Beasts. The remaining species now dwell on floating islands high above the ground, safe from all but the most agile of these creatures. However, this new haven, Regul Aire, harbors a sinister secret. Only a select group of young girls, known as Leprechauns, possess the ancient weapons required to defend against invasions by these beasts. Into their tumultuous and transient lives enters an unlikely hero: a young man who lost everything in his final battle five centuries ago, the sole surviving human reborn from a long, frigid slumber. Unable to fight anymore, Willem takes on the role of father figure for the girls he never had, caring for and nurturing them as they struggle with their own feelings of helplessness and loss. As they interact in an orphanage, Willem and the girls gradually come to understand what family means and what truly matters in life. Despite his newfound limitations, Willem remains determined to protect those he loves, even if it means waiting for them to return home from battle, as his daughter once did for him so long ago.