This Bearer wishes to echo your sentiments, Receiver, in every particular. Usually an expression of accord, whether in harmony or disharmony, Likewise can be as useful as an affirmation (to You rock! or I love you for example) or as a warning (in response to Jealousy, This means war! or You shouldn't have done that). It can be polite (sent in acknowledgement of Nice to meet you) or critical (a comeback to Don't make promises you can't keep or I don't trust you). Responses evidently vary according to the tone of the exchange, but We need to talk, Evil laugh, How could you?, Is this the end?, Aaaaaaaaaa or Whatever may all be useful.