The emoji has another name, “pleading face”. This is basically how it became to be used by bottoms. Tops don’t plead, but bottoms do.

There’s lots of emojis that the culture has given alternate meanings to, for example the peach and the eggplant.

You could ask “how would I explain this to a child” to anything adults talk about that is sexual in nature. Usually the answer is “don’t.”

I don’t think TFA was written for children and the author wanted to include this common internet meme in to their article title.