Dylan's current girlfriend Brianna isn't, um, a very nice person, to put it mildly. In the pilot episode, she not only seems to be verbally abusing and intimidatingly bullying Erin but also catfishes Erin into thinking that she was a genuine date for her instead. After luring Erin into the woods, she brutally beats Erin out, all while her gang – including Dylan – cheeringly laughed and filmed the whole debacle. Given the documented evidence, she's currently in police custody for her violent tendencies toward Erin. Although, it seems unlikely that she would create the whole scene and attract all the attention to herself right before, if she were planning at all, killing Erin. So far, we haven't had enough signs of her being the culprit. Let's put a pin to her name till then, shall we?