GEKI SHIN/JU XIN
Japanese Pronunciation: Geki Shin
Chinese Pronunciation: Ju Xin
2.Activities in History
Ju Xin was born in Zhao and moved to Yan when King Zhao of Yan(燕昭王) was openly recruiting talents from all states in China due to the chaos in the state of Zhao during the Shaqiu revolution by Zhao Zhang, son of King Wuling of Zhao.
He then fought under the Yan banner and led the coalition army to attack Qi with Yue Yi(Gakuki). He temporarily disappeared from history until the year he was slain by Pang Nuan(Houken), who used to be his good friend when he was in Zhao. Entries of his records in Shiji as below:
1) Shi Ji, Chapter 34–Aristocratic Family of Duke Zhao of Yan：
King Zhao of Yan ascended the throne after Yan was destroyed(by Qi), he offered a huge reward to recruit talents. …… Yue Yi arrived from Wei, Ju Xin arrived from Zhao and many others moved to Yan as well. The king of Yan mourned the dead, consoled the orphans and promised to endure the hardships with his people.
十二年，赵使李牧攻燕，拔武遂、方城。剧辛故居赵，与庞煖善，已而亡走燕。燕见赵数困于秦，而廉颇去，令庞 煖将也，欲因赵獘攻之。问剧辛，辛曰：“庞煖易与耳。”燕使剧辛将击赵，赵使庞煖击之，取燕军二万，杀剧辛 。
12th year (of King Xi of Yan’s rule, 243BC), Zhao ordered Li Mu to attack Yan, capturing the cities of Wusui and Fangcheng. Ju Xin used to live in Zhao and were good friends with Pang Nuan before he went to Yan. The king of Yan noticed that Zhao was defeated by Qin several times recently, and with the departure of Lian Po, they sent Pang Nuan to lead their army. He wishes to attack Zhao while they are still recovering from the recent wars. He asked Ju Xin about Pang Nuan, in which Ju Xin replied that he is very easy to deal with. With that, the king of Yan sent Ju Xin to attack Zhao. Zhao sent Pang Nuan to defend against the attack which resulted in the capture of 20,000 Yan soldiers and the death of Ju Xin
2)Shi Ji, Chapter 13–Book of Zhao Aristocratic Family：
Third year (of King DaoXiang of Zhao’s rule, 243BC). General Pang Nuan attacked Yan, capturing their general Ju Xin.
As recorded above in the different chapters of Shiji, the clash between Pang Nuan and Ju Xin had some minor discrepancies in terms of who was the attacker and whether Ju Xin was killed of captured(or captured and killed).
While Ju Xin and Pang Nuan might seem like they are in their 30s or 40s in the manga, they are in fact in their 70s during the final clash.
It is speculated that Ju Xin was not regarded highly by the new king(King Hui) after the death of King Zhao of Yan. He was then never sent to any war until the era of King Xi of Yan. It is also possible that his battles were not recorded as most of the wars involving Yan during the reign of King Hui(and a couple of kings later) were focusing on the victories of Qi, led by their legendary general Tian Dan, who manage to recover all territories of Qi after the coalition war against Qi.