Originating from Montgomery County, Maryland and a few individuals of AEHS Class of 2004, it's a combination of "Shit" and "Rawr" (Roar).
Commonly used to emphasize anger
, and just about anything really.
Shar can also be used as a verb in different aspects. Refer to the last example for this.
Agent A: Maaaaaaaan ... my roommate is such an asshole. He cockblocked me while I was flirting with Anna from down the hall... ShaR~!
The child exclaimed shar in response to everyone's ignorance.
Are you shar you are going to take a shar-ar now?