裏切りは僕の名前を知っている - Season 1 Episode 16

Takashiro invites Yuki to accompany him on a stroll through the gardens. Passing through a bamboo grove, Yuki feels a sense of nostalgia towards the place. When Takashiro winces in sudden pain, Yuki gets to know more about Takashiro's real self: Takashiro is harboring a Duras within himself, enabling him to heal his wounds and making him immortal and renewing his memories. Takashiro has actually lived for more than 1000 years and was present since the start of the battle. He proceeds to tells Yuki that he was not related by blood to Yuki and that it was a lie to gain Yuki's initial trust. The reincarnation of the Zweilt guardians are also due to Takashiro summoning their souls back into the world in order to participate in the battle. Receiving empathy and understanding from Yuki who assures Takashiro that he remains an important person to him even if they do not possess blood ties, Takashiro brings Yuki to a monument which is known as God's Stone, the source of the Giou family's powers. There, he explains the origins of Reiga who was born from a union between a Giou-clan mother and an Opast father, making him a forbidden child. Reiga's main intent is to destroy humans as he views them as not fit to live. Takashiro mentions that Reiga who was reincarnated as Kanata holds no memory of his past self before his awakening, assuring Yuki that the Kanata he has spent his childhood with is not a set up facade. Relieved, Yuki confronts Takashiro to reveal the event that causes Reiga to betray the Giou clan.