Rengoku Kyoujurou led the mission given by Reiger and left.
He promised Reiger that he would bring back a large amount of Scarlet Crimson Sand Iron and Scarlet Crimson Ore.
The amount of Scarlet Crimson Sand Iron and Scarlet Crimson Ore was substantial; not a single member of the Demon Slayer Corps was without a Sun Wheel Blade. Even Tanjirou received a new one immediately after his broke, which proves that the Demon Slayer Corps weren't lacking in materials for swords. What they lacked were swordsmiths with superior forging skills.
However, this time Reiger did not need anyone to forge a sword for him; he just needed the raw materials for the blades. This request was still not too difficult to fulfill, and Rengoku Kyoujurou said that he would bring back more for him with the lord's permission, showing that he was really considerate.
"Thank goodness the first Pillar I met was from the Rengoku family. Otherwise, it wouldn't have been so easy to talk with anyone else."