grammar - Can "masters" (plural) be used to refer to a single entity?

I was perusing the forums of a video game I play. I began reading a thread about the lore of the game, because a few things lore-wise are left pretty vague. Two individuals got into an argument about the use of the word "masters" by a character in the game.

The sentence is as follows:
Character: "The Tenno will surpass their former masters."

Now, guy A says that "masters" is referring to a single entity & Tenno is inclusive of the guy saying it. Guy B says, no it's plural so it's referring to multiple people.

So, to elaborate on my question, is there ANY way whatsoever that "masters" in it's plural form could be used in reference to a single person? The reason I'm bringing this question here is because, based off the lore provided & inferences made by the player base & typically agreed upon by the majority, it is believed that the "character" is inclusive in "The Tenno" (that's part of that vague lore I mentioned earlier). Their was a group several hundred years ago that were the masters of the Tenno (which are a faction btw), but now, more recently, they have a single master, a single entity. I'm sorry if none of this makes any sense or I've provided a bunch of extraneous details.

If all of that is too confusing guy A made this statement: "It's quite possible syntax-wise to mention a singular object as plural. Trust me, I'm a linguist." (I think he meant to say "to mention a singular object with a plural word). Is this possible?

Thank you for your time. I can provide a link to the forum page if desired.