Shinohara Akito

Nanahoshi Shizuka's friend and one of the two people Rudeus was not able to push out of the way from the truck before he died in his previous life.

Volume 22 - Young Man Period - Organization Chapter
He did not actually appear in the volume, but was mentioned by Nanahoshi. Nanahoshi created a hypothesis that he was also summoned to this world, but was summoned into the future where he saved a weak fated Miko that was destined to die. That Miko had the power to rewind an object's time and Akihito possibly saved that Miko and met with Orsted as Nanahoshi did to create a device that would amplify the Miko's power to change the past. If the future is changing the past, the future would take precedence and be the reason why Nanahoshi can't go back to her world since she may have been summoned by Akihito during the Metastasis event so that she can create the Multiverse teleportation device and go back to her world with him in the future. Since her future self that went back with Akihito can't exist if she went back to her world in the present, Akihito's influence interfered with the device when she was attempting to go back home.

In Rudeus's inner monologue, he summarized the details of the proposed future. Akihito collaborated with Orsted and was able to determine the reason why he would be unable to win against Hitogami. Akihito altered the past with the saved Miko's amplified power which may have been the reason Hitogami saw a vision of Rudeus's descendants with Orsted and an unknown man killing Hitogami and that the unknown man might be Akihito. Then in order to go back home, he caused the Metastasis event that summoned Nanahoshi so that she would create the device that would send them back to their world.