I got a really juicy idea related to Varka.
What if, on the night before all the knights go on the expedition, Varka and reader (afab) (let's say a barmaid that he was developing a crush on) had both gotten drunk and ended up in the man's home together.
The morning after she fled, and Varka himself doesn't remember shit. He basically got himself actually drunk enough to forget.
Well months pass by and uh oh! Reader finds out they're pregnant!
Now, a reasonable person may end up writing a letter to tell the father right? NOPE, NOT THIS IDIOT. Instead they fled Mondstadt all together, not wanting anyone to discover that they and the Grand Master had a night together.
Now time skip to where reader arrives to Nasha Town with her almost ten year old son, a young boy who looks almost EXACTLY like a copy of Varka. Like even his build makes people confuse him for a teen because he's so tall and wide, and his strength doesn’t help.
In my mind I would think reader never looked at any news of Mondstadt or the expedition, so they didn't even realize it was in Nod-Krai now. It's only when someone, most likely a bartender at The Flagship, confuses the son with his father.
After some shenanigans of reader being on high alert, and their son being confused because reader had only told positive stories about the knights and the Grand Master himself (but was never told he was Varka's son, reader planned to take that to their grave). Finally Varka catches sight, instantly recognizing the reader and also making a easiest connection that the boy is his.
And now he's confused and devastated that he missed so many years of his son's life, which is what reader was trying to avoid! Varka had a mission and he needed to go, not be held back because of a drunken mistake!
That's all I got, but I really do want to write this. Just gotta come up with a name. Cause I imagine reader named their son after Varka. I thought of Vardulf (Bardulf but with a V instead) but idk if that's too on the nose or not.