L'Arc Berg Sickle/Chronology

Volume 5
He was first introduced when Naofumi and his companions boarded the ship to sail to Cal Mira. Together with Therese Alexanderite, they, at first, didn't believe that Naofumi was the Shield Hero, as he didn't seem to fit any of the bad rumors circulating around the shield hero and also because they already ran into or hunted a number of fake shield heroes capable of changing shields (hired by the Church of the Three Heroes to ruin Naofumi's reputation). He advised Naofumi to stop pretending to be the shield hero, as people may dislike him. Naofumi eventually gave up in trying to convince them of him being the shield hero.

They agreed to level up together on the island after two days. They grew worried about Naofumi when he didn't return for the night and went to search for him. Naofumi was getting too comfortable with them. Before going to level up together, L'Arc told Naofumi that the four holy heroes are on the island and that he found the Shield Hero, curious Naofumi asked who he thought the Shield Hero was. L'Arc pointed at Mald, much to the dismay of both Naofumi and Raphtalia. Both agreed that Mald is the type to cause problems. While leveling together, both sides were impressed with the others. L'Arc and Theresa began to suspect if Naofumi really was the shield hero while Naofumi wished to have them in his party.

During the fight against the wave, he concluded that Naofumi really was a Cardinal Hero and tried to kill him. Though their target is all the four holy heroes, he didn't believe the other three as Heroes. They still couldn't completely beat Naofumi even with the help of Glass and so had to return to their own world.

Volume 7
In the next wave, they again traveled to the other world. When they wanted to return to their own world, they encountered Kyo, who was another wielder of a vassal weapon of their world but tried to rule the worlds instead of following his mission. Their Vassal Weapons begged them to stop him. Thus they stayed in this world and tried to stop him. By this time, they heard of the Spirit Tortoise defeat(The decapitation of the head, but not truly dead) by Naofumi and accepted the fact that he was a capable hero despite being enemies.

During Naofumi's second fight against the Spirit Tortoise(Regenerated its head) he met Naofumi again. He first encountered him when Naofumi tried to travel to the heart of the Spirit Tortoise and Naofumi begin to attack him without listening to his explanation. But before they could finish a decisive blow, they were separated by a living wall. After that, they met him again during the battle against Kyo. He then explained to Naofumi, that he didn't have any intention to fight against Naofumi now, only that he had to fight along with him against Kyo.

Volume 8
Because Kyo managed to escape after the battle, they tried to chase him in the other world. After they were transported to L'Arc's world, Naofumi and Rishia were separated from the rest and so they tried to search for them.

They landed in the enemies' land and were thrown into prison. Using Raphtalia's magic they managed to escape. After being reunited with Kizuna and Naofumi, they were lectured by Kizuna, who heard what they had tried to do in the other world. After that, they once again fought against Kyo and finally beat him.