Grawlix is the new all-purpose word to express whatever you want to express, and the reader is invited to interpret it any way he/she wants.  It's an allowable form of expression because the powers-that-be use the word, too.  If the reader has a polluted mind, well, then grawlix might be something nasty.  Or it might not.  If the reader is of pure mind, then they can't complain because it was meant to be a pure adjective.  Right?  Just make sure that grawlix is spelled correctly and doesn't have any nasty symbols in place of the w, x, or whatever.