Stories of the Japanese 00962 [Early Northern and Southern Courts Period] The Change of Heart of Akura Nobutane

Although it was decided to send Wakiya Yoshisuke to Iyo Province, the route there, both by land and sea, was entirely through enemy territory. While they were discussing how to get to Iyo, Akura Nobutane, a resident of Bizen Province, sent a messenger who conveyed:
'Last month, when I raised an army on Shodoshima (Shodoshima Town, Kagawa Prefecture), the loyalists in the province joined me. We have already defeated the rebels and secured the sea route. Please send your commander as soon as possible.'
Hearing this, the members of the Yoshino court rejoiced, saying, 'At last, we have been blessed by heaven.'
Now, Akura Nobutane was supposed to have been a Northern Court warrior as of 1335 (see episode 00842). When did he become a Southern Court supporter?
Here, the 'Taiheiki' introduces the reason why Akura Nobutane betrayed the Northern Court. It claims it was over a woman. It sounds like a fictional story, but let us introduce it.
There was a warrior named Ko no Moroaki, a cousin of Ko no Moronao. A woman named Osai, who was a concubine of this Moroaki, became the cause of the trouble.
Osai was known as a beauty and came from a good family, but she spent many days without being able to find a partner to settle down with, until eventually, she and Ko no Moroaki became attracted to each other.
However, this Ko no Moroaki was appointed as the Governor of Ise and had to leave Kyoto to take up his post. Moroaki had a wife and children in Kamakura, and he wanted to call them to Ise and live with them, including Osai. Hearing that his legal wife in Kamakura was a very jealous and strong-willed woman, Osai inwardly began to dislike the idea of going to Ise.
Moroaki persistently persuaded Osai, and with great effort, he was finally able to get her into a palanquin to take her with him.
When the palanquin crossed the Seta Bridge (Otsu City, Shiga Prefecture), a gust of wind blew the blinds up, and it was revealed that an old woman of about 80, full of wrinkles, was riding inside. Surprised, Moroaki asked, 'Have I been bewitched by a tanuki or a fox?' The old woman replied,
'I am not a monster. I have served Lady Osai for many years, and I only rode because Lady Osai told me to.'
Moroaki, regretting that he had been 'deceived by that woman,' returned to Kyoto to look for Osai, but received information that she had married Akura Nobutane. Enraged, Moroaki began planning to kill Akura Nobutane.
Hearing that Moroaki was plotting his murder, Nobutane had nowhere to hide and was forced to abandon the Northern Court and join the Southern Court. Thus, the Northern Court lost a loyal subject for a trivial reason.