"On my way!" Is a term that expresses either extreme sarcasm or enthusiasm towards being on one's way to a place. It can be said with or without intent, as the keyboard shortcut ‘omw’ may make someone say this unintentionally. In the cases this happens, it is a very traumatic scene that is very real in our world today.
“im On my way! rn”
“On my way!”
“How could you.”