↑Gagouji would refer to Gangoji, a temple that Soga no Umako built, which was known to be haunted by an evil spirit called Gagoze, killing apprentices. There was a tale that tells of a child given to a farmer by a thunder god, who, upon growing up, once got rid of Gagoze from Gangoji. Refer to Touhou and Japanese culture#Gagoze for more details.
↑ 2.02.1雨の磐舟 is a pun of 天の磐船 "ame no iwafune". According to legend, Nigihayahi no Mikoto, the founding father of the Mononobe clan, descended from heaven in the rock ship "Ame no Iwafune".
↑ 3.03.13.23.3In the Nihon Shoki, it's said that when Emperor Jimmu was invading Yamato, he made 80 ceremonial shinto dishes with the soil of Mount Amanokagu, and thanks to his praying with them won the battle. Emperor Jimmu was later close to Nigihayahi-no-Mikoto, a distant ancestor to the Mononobe clan.
↑Haibutsu Kishaku, the anti-Buddhism campaigns that happened several times in Japan's history, in which many temples and statues were burned
↑Sakuraiji, built by Soga no Iname (Tojiko's grandfather), was said to be Japan's first proper Buddhist temple, but it was burned down by the anti-Buddhist Mononobe clan.
↑ 6.06.16.26.3A seidoujo (聖童女) is a girl before her first period (around ten-year-old) who is tasked to serve food to the sun goddess, Amaterasu. Oomonoimi-no-Kami (大物忌神) is a god of purification and protector of Japan, who is believed to be the same as Toyoukebime, an important goddess of agriculture and food who serves food to Amaterasu.