Doesn't make the phrase any less ridiculous. Dev could have used any other term to mask the relationship. But we're stuck with "Landlady" because it's a fucking meme at this point. Hell if it's the game's description and it's editable why not just make that clear in the description?
Saying "landlady" does nothing but serve as a juvenile attempt to thumb the nose at Patreon for banning incest. "Oh haha, she's TOTALLY not your Mom. The landlady, who never asks you for rent payments, has just raised you since you were a baby. That's definitely normal and not weird at all." It's not like we need secret code to know when a game's relationships are intended to be incestuous. It's pretty obvious.