♗ - Their first relationship.
Stages of Life Headcanons
This really depends on how you define a relationship. I’m going to assume this refers to a romantic relationship. But what exactly defines that? He might have had a crush when he was younger, but would that be considered a relationship? Yao was pretty emotional when he was younger, and fell into infatuation relatively easily. But which one of those actually count?
As for his first friendship that had any romantic connotations, probably some time during the Shang dynasty. He was maybe about 12? He really just wanted to hang out with this peasant girl that lived near the capital, but she was scared to death when guards had come after him - since the last emperor was feared for his cruelty and tyranny. Her parents didn’t let her see him again, because they didn’t want her to have any connection to the court. Though, you could argue that was just a friendship as well?
There was also a girl who took care of him during the warring states era. From when she discovered him in his abandoned-looking home to her death, she visited him to make sure he had something to eat and drink. He did wish that he was more well, and would do what he could for her, little favours, when he was able to get out of bed. He probably had a bit of suppressed jealousy when she got married, but got along with her husband well, so?
During the Han dynasty he may have had a crush on Lien? But again that does not really count? Considering how the Chinese domination of Vietnam was a lot of ransacking... And that didn’t exactly create a great relationship to begin with. If he did like her he probably didn’t realise it either. And during the Jin dynasty there was once that the royal court tried to marry him off to a rich family but his fiancee committed suicide on their wedding day. So he didn’t even get to meet her.
During the Southern and Northern Dynasties, he probably got quite a few men asking offering their daughters’ hands in marriage, all of which he turned down, because by then he understood that he probably couldn’t have biological children, and would definitely not benefit them in any way. He got along with their daughters though, and sometimes had to avoid them because their actual husbands might be a little... upset... if he spent too much time with them.
And then of course, is his first marriage -- to Li Lihua, a princess of the Tang dynasty. And I think I have a lot of headcanons on her already so.
// lies down I wish this meme was more specific.