lactic acid bacteria
In an episode of Rozen Maiden, Suigintou makes a rather unusual remark when, while taunting the other dolls, she asks them if they are "taking their lactic acid bacteria" (in the form of probiotic drinks), implying that they are weak and that nutritional deficiencies might be the reason.
Since this joke sounded strange and out of character it was turned into a meme.
