Yuroi and netsuni are kid siblings. Yuroi controls lava, fire, and lava rocks. Netsuni controls the sea, sea creatures, etc. They both have a sword in which they use in case of battle. Matsuka/matsuko (matsu) is their genderfluid half sibling. Matsu conquers land, trees, vines, plants, roots, etc. He uses a staff in which he uses to fight a battle. The three of them fight many battles throughout the events in the story. Matsu, the half sibling was named after netsuni and yuroi's father, matsuko. Matsuko kicks his wife, rin, out after finding out she had cheated on him and was pregnant with another man's kid. Rin gave birth so matsu, she named him after her late husband. Matsuko (rin's husband) died of illness and that's when rin named the baby.