if it's the line I'm thinking of, it basically ties into a little known Meme about her being stacked as the mix of 99 being the number of planes and how the wording resembled Konyuu (whever the big boob word is)
[...] how the wording resembled Konyuu (whever the big boob word is)
Kyonyuu, spelled 巨乳 ("giant breasts"). It makes me chuckle because 巨 is the same kanji used to spell "titan" in Attack on Titan (進撃の巨人, "attack of giant people").
It.... will fall out...This is actually part of her secretary line so you can assume what is going to falling out