Takeru was the son of ghost hunter and Daitenku Temple owner, Ryu Tenkuji and his wife Yuri Tenkuji, who died after Takeru was born. After the death of his father at the hands of Royal Gamma Adel, he was entrusted with the duty of a ghost hunter as Ryu passed on Miyamoto Musashi's hand guard to Takeru. He was also placed under the care of Onari, one of the Daitenku Temple's monks.

Takeru would spend several years in his late father's lab studying the Stories of the World's Greatest People to become a ghost hunter, but eventually felt closer to despair when he wasn't able to witness any of them. On his 18th birthday, he was mailed a blank Ghost Eyecon from his late father, which was sent in October 2005, allowing him to see ghosts but at the same time becoming a target of Katana and Yari Gamma. He boldly faces them, but his lack of combat training eventually leads to his own death. He was soon revived as a ghost by Sennin, giving him a Ghost Driver and the duty to collect all 15 Heroes' Eyecons to revive himself within the period of 99 days. He was also entrusted with Yurusen, a small phantasm that would teach him how to use his powers. Now as the warrior Kamen Rider Ghost, he utilized his newfound power to fulfill his role as a Ghost Hunter to first defeat his murderers and then to prevent more targeted civilians from becoming sacrifices of the Gamma. To further assist Takeru, Onari forms an investigation group called the Mysterious Phenomenon Institute that bends on solving paranormal cases that may be related to the Gamma.

After recovering the 15 eyecons and freeing the Genma from their worlds cycle of death Takeru was given the chance for rebirth from the Great Eye, he refused but ultimately got his second chance at life, and while he is alive now he has inherited the role of Guardian of the Afterlife review all those who pass on to determine weather they too can get a second chance as he once did or moving on to their deserved afterlife.