*Translation revised with the generous help of Ofer Waldman – thanks Ofer!*
The Tang-era Vice-President of the Ministry of Personnel Li Yuangong had a granddaughter, a Miss Cui, peaceful of countenance and extremely beautiful, fifteen or sixteen years old, who was suddenly afflicted by a demonic illness. When this had lasted for a long time, the fox manifested itself as a young man, calling himself ‘Gentleman Hu’; they repeatedly sought scholars of magic, but were unable to make it go away. Yuangong’s son possessed a broad education and great wisdom, and often asked: “Does Gentleman Hu also possess learning or not?” And so the fox engaged in discussions, missing not a single topic. He employed many questions to probe the fox, who tended to be closely acquainted with music. After a long time of this, he addressed Miss Cui, saying: “Nobody should remain without education.” He therefore brought an elderly man to teach Miss Cui Classics and History, and over three years she acquired a degree of expertise  in the cardinal principles of the various schools. He also brought a person to teach her calligraphy, and, after a single year, she came to be considered an expert calligrapher. He also said: “How can a married woman not have studied music? The konghou and pipa, though present in all music, are not so suitable as study of the qin.” He further summoned another person, saying that he was skilled at playing the qin, and stating that his surname was Hu, and that he was a scholar of Yangdi County in the Sui era. He taught her all the various tunes, preparing her fully in their subtleties, and she was quite unsurpassed on other famous songs. As to himself he claimed: “I am skilled at Guanglingsan, which many encounters with Ji Zhong San did not get him to teach it to other men.” He was also especially good at transmitting the wonders of Wuyeti. Li later asked: “Why does Gentleman Hu not marry and return home?” The fox was extremely pleased, bowing again in thanks and saying: “I have long cherished this, too, but have not dared, purely due to being a pleb” That day, he bowed over and over to the family, leaping about in the utmost joy. Li asked: “Mr Hu wishes to return home with his wife; where is his residence?” The fox said: “Before the residence there are two large bamboos.” At that time the Li residence had a bamboo garden, and Li, going to search around there, found a small hole between two of the great trees; it turned out to be a fox’s lair, drawing water to fill it. At first they captured a badger, a raccoon dog, and several dozen small foxes. Eventually an elderly fox, wearing an unlined green robe, followed them out of the hole; it was the same robe he was always wearing. The family spoke joyfully: “Now Mr Hu has emerged!” They killed him, and the strange events stopped.
From Guangyiji 廣異記 (Extensive Records of the Strange)
Li Fang 李昉, et al., Taiping guangji 太平廣記 (Extensive Gleanings from the Era of Great Harmony), ix, 449.3671-72:
唐吏部侍郎李元恭。其外孫女崔氏。容色殊麗。年十五六。忽得魅疾。久之。狐遂見形為少年。自稱  胡郎。累求術士不能去。元恭子博學多智。常問胡郎亦學否。狐乃談論。無所不至。多質疑于狐。頗狎樂。久之。謂崔氏曰。人生不可不學。乃引一老人授崔經史。前後三載。頗通諸家大義。又引一人。教之書。涉一載。又以工書著稱。又云。婦人何不會音聲。箜篌琵琶。此故凡樂。不如學琴。復引一人至。云善彈琴。言姓胡。是隋時陽翟縣博士。悉教諸曲。備盡其妙。及他名曲。不可勝紀。自云亦善廣陵散。比屢見嵇中散。不使授人。其于烏夜啼。尤善傳其妙。李後問。胡郎何以不迎婦歸家。狐甚喜。便拜謝云。亦久懷之。所不敢者。以人微故爾。是日遍拜家人。歡躍備至。李問胡郎欲迎女子。宅在何所。狐云。某舍門前有二大竹。時李氏家有竹園。李因尋行所。見二大竹間有一小孔。竟是狐窟。引水灌之。初得猯狢及他狐數十枚。最後有一老狐。衣綠衫。從孔中出。是其素所著衫也。家人喜云。胡郎出矣。殺之。其怪遂絕。出《廣異記》
The version found in Guangyiji is essentially identical; here is the Chinese text, from the combined volume Tang Lin 唐臨; Dai Fu 戴孚, Mingbaoji; Guangyiji 冥報記 / 廣異記 (Records of Netherworld Vengeance / Extensive Records of The Strange) (Beijing: Zhonghua Shuju, 1992), pp. 203-4:
唐吏部侍郎李元恭，其外孫女崔氏，容色殊麗，年十五六，忽得魅疾。久之，狐遂見形為少年，自稱胡郎，累求術士不能去。元恭子博學多智，常問：「胡郎亦學否？」狐乃談論，無所不至，多質疑于狐，頗狎樂。久之，謂崔氏曰：「人生不可不學。」乃引一老人授崔經史，前後三載，頗通  諸家大義。又引一人教之書，涉一載，又以工書著稱。又云：「婦人何不會音聲，箜篌琵琶，此故凡樂，不如學琴。」復引一人至，云善彈琴，言姓胡，是隋時陽翟縣博士。悉教諸曲，備盡其妙，及他名曲，不可勝紀。自云：「亦善《廣陵散》，比屢見嵇中散，不使授人。」其于《烏夜啼》尤善，傳其妙。李後問：「胡郎何以不迎婦歸家？」狐甚喜，便拜謝云：「亦久懷之，所不敢者，以人微故爾。」是日，遍拜家人，歡躍備至。李問：「胡郎欲迎女子，宅在何所？」狐云：「某舍門前有二大竹。」時李氏家有竹園，李因尋行所，見二大竹間有一小孔，竟是狐窟，引水灌之。初得猯狢及他狐數十枚，最後有一老狐，衣綠衫，從孔中出，是其素所著衫也。家人喜云：「胡郎出矣！」殺之，其怪遂絕。
 On Li Yuangong 李元恭 (d. c. 702 CE), see CBDB Person ID 0195948.
 On this piece of music, see https://zh.wikipedia.org/wiki/%E5%B9%BF%E9%99%B5%E6%95%A3.
 On this piece of music, see https://zh.wikipedia.org/wiki/%E4%B9%8C%E5%A4%9C%E5%95%BC.