Yami no Naka no Crown
Each in the world is born with two things: the ability to assemble the light of life and the vessel of light to collect and store it. Most people use their boats to help them perform various tasks, but sometimes someone is born with a boat that allows them to fight. The main character, room, stumps at the end of the battle only in order to find the survivor. Can a young man who she saved, be associated with the people of the king, who entered the city with the intention to kill everyone?