![1boy 1girl arm_at_side bangs black_serafuku black_skirt blonde_hair blouse changpao chinese_clothes closed_mouth dark_skin feet_out_of_frame gem glint green_eyes hair_behind_ear hanfu hekisoujo_(juuni_kokuki) highres holding holding_sword holding_weapon juuni_kokuki keiki long_hair long_sleeves looking_at_viewer midriff nakajima_youko orb pleated_skirt red_hair rui_yuda scabbard school_uniform serafuku sheath skirt standing suiguutou_(juuni_kokuki) sword tassel tied_sleeves torn_blouse torn_clothes torn_skirt torn_sleeves unsheathed very_long_hair weapon rating:s score:1 post #3699147](/cdn_image/preview/f4/9d/f49d9b4e6efb397de56a9e722f77d7f9.jpg)
Suiguutou (水禺刀 Water Monkey Sword; Sword of Suiguu) is a sword that can be wielded only by the rightful ruler of Kei. The sword is accompanied by the Hekisoujo, a miraculous gem possessing healing powers. The sword, along with its scabbard, and the gem are sacred treasures in the kingdom of Kei.
The Suiguutou was forged by Tatsu-Ou, a previous great ruler of Kei, from a water youma and it was originally known as Suikantou (水鑑刀, Water Mirror Sword). When Tatsu realized the sword's power could bewitch the wielder, he forged a scabbard to contain its magic. Because the scabbard was made from a long-tailed monkey youma, the sword was renamed Suiguutou to reflect its new nature. The sword and scabbard change form with each new master; the blade originally took the form of a long-handled scimitar and eventually becomes a long sword for Youko Nakajima.