The last few weeks had been quite a whirlwind. You moved to a far away land, the local "princess" had introduced you to a nice but lonely woman who showed you around, you two hit it off, and before you knew it you were waking up in her embrace. The fact that she towered over you hardly mattered, her sweet and kind demeanor had won you over from the start. You were still curious, though.
"Have you always been so... uh... big?"
She giggles a bit. "No actually. That's another quirk of this place, actually. See, there's this ancient saying that translates to something like 'May you always rise to the expectations of others'. Only, it's not just an expression: it's more of a blessing on the kingdom and its denizens."
"Some say it's a gift from Celestia herself, but I think it's older and deeper than that. Regardless, the result is that anyone you might expect to be an authority, and leader or someone else of significance tends to be of a larger stature."
"So you've grown because you're a teacher?"
"Something like that. It seems like every year as my students grow up, I keep pace."
"I guess it just wouldn't do to have some jerk of a teenager hit 6 foot and start looking down on you, would it?"