mo was originally a nickname for "emotive hardcore" (type of music), but has evolved into meaning "emotional" because it was misinterpreted, since fans of this music were ususally known for being a bunch of depressed-self-harming-teens with too much free time. It's all stereotypical. But this is what it's known for now. An emo person (like I said stereotypical) would be very depressed, hate the world, including themselves and probably cry all the time. They've even stereotyped and emo style. Usually "emo" kids dress in skinny jeans, dark colors (but not all black), band tee shirts, and chucks. But, like I said about 5 or so times. IT'S ALL STEREOTYPICAL!!! And it did originally mean "emotive hardcore". (and if some one dresses like that it doesn't mean they're gonna go suicidal!)
an Emo thought "the world hates me im gonna cry and cut myself"