The Thorn Fangire appeared in 2009 TV series called Kamen Rider Decade. Her real name is Yuki (ユウキ Yūki) who was the Queen of the Fangires from the World of Kiva. Her true form was the Thorn Fangire (ソーンファンガイア Sōn Fangaia), whose true name was Perishing at the Altar, Silence from a Deep Kiss (滅びゆく祭壇に、沈黙より深いキスを Horobiyuku Saidan ni, Chinmoku yori Fukai Kisu o).
She was a sea cucumber Fangire that belongs to the Aqua Class (アクアクラス Akua Kurasu) Tribe and able to execute her own version of the "Final Zanvat Slash". Though she supports Wataru, Yuki actually sides with Apollo Geist, marrying him to give him immortality so she can have a place in Dai-Shocker. When Tsukasa crashes the wedding, the Thorn Fangire fights him and is killed by Decade Complete Form with Ryuki Survive's power.