The joke here is that, in Japanese, "fraternal/identical twins" involves words that mean "eggs" and some others that phonetically sound like "sausages".
You may remember Konata also doing this in the LS anime.
Wouldn't people usually think of us as just normal sisters?Somehow my intuition told me that you were twins~...Fraternal twins differ from identical twins in that they can have different appearances and personalities-*nonchalantly*Intuition!?Ah, but,Oh, those two were probably identical twins, right?For Tsukasa and I, we're fraternal twins.Dammit! Are those two on the same wavelength or something!Hahー*grrrowl*But still, how did you know that we were twins?then again maybe it's because I saw a pair of twin beauticians earlier.That's amazing!!All that talk about eggs and sausages made me hungryーOh, I know! I totally understand how you feel!