POSSIBLE SPOILER: Gonna take my guess at the hidden plot at this point involving Lizzie. She's a Cagaster that has been suppressed(reversed?) back into a human by her father (or a rogue scientist). She was the one that attacked him when she started turning and then he suppressed it while escaping with her. Potentially the government is experimenting on what causes Cagaster transformations and she is either an attempt to cure or a test subject made into a Cagaster intentionally. Potentially she'll get taken away here and the plot will follow Kidou as he goes on a quest to save her (think Zelda).