WYF is not necessarily a harmless slang among children since it typically requires the information about the location that is rather personal. When children reply with information such as their city, school or neighborhood, they are putting themselves in internet dangers, such as strangers who claim ill will. The slang is not an offensive term, but the context of the question does not allow children to respond to it. Children are not supposed to provide details but they should be shown how to be safe with the internet. Know more what does wyf mean in text