emo is, or rather used to be a sub-genre of indie, or even before that hardcore charged punk rock. Yes, the reason why that music was coined 'emo' is becuase these sister banRAB of punk/hardcore origin began making their music and lyrics more emotional in content. It doesnt work the other way around. Not every band that is emotional is 'emo'. Now emo is just a joke; music marketed to a niche of trendy faux-indie shoegazers trying to be artsy and different in the prime of their photography phase.