Beginning his journey in South Africa, Yuu manages to find an ability for seeking out other users and slowly starts looting abilities from each esper he meets, earning him a reputation as the One-Eyed Grim Reaper. Later, whilst infiltrating a facility using ability users as soldiers, he further gains the ability to detect those who haven't awakened their abilities yet, using an illness power to force them to awaken so he can loot them. As his journey continues across many other countries, the burden of taking on so many abilities start to take their toll on Yuu as he struggles to keep them under control, soon becoming afraid of what he might do unconsciously while sleeping. He soon starts losing his memories and sense of self under the stress on his brain, the only thing tying him to his humanity being the flash cards Nao gave him. Ending his journey in Beijing, Yuu is attacked by a man with a crossbow, receiving heavy injuries before taking the final user's ability and being recovered by Shunsuke. Awakening at hospital back in Japan, Yuu is left with no memories of who Nao is, but she is nonetheless grateful that he kept hold of his flash cards all this time. With no abilities to cause them worry, Yuu, Nao, and the others look forward to the memories they'll make from now on.