Adventure Club (冒険部 Bōken-bu?) or properly referred as Nanae Island Third High School Adventure Club (七重島第三高等部 冒険部 Nanae-Jima Dai San Kōtō-bu: Bōken-bu?) is one of the prominent organizations in Nanana's Buried Treasure series.
The adventure club was actually organization created by Kasumi Konjō―one of the GREAT7―to those who taken interest of Nanana Ryūgajō thanks to renting the room of 202 at the Happiness Dorm of Nanae Island, and read the Nanana Manual written by Konjō herself. The club's main objective is currently unknown, but it is supposed to be collecting the Nanana Collection.
- Isshin Yuiga ― Third president.
- Yū Ibara ― Isshin's vice-president.
- Jūgo Yama ― Member
- Tensai Ikkyū --- Member
- D'arc Hoshino --- Member
- Kagetora Tsurezure --- Member