The Testament of Sister New Devil
Reunion and a Gap in Trust
S1 E3:
Basara's childhood friend Nonaka Yuuki warns him not to get involved with Naruse Mio any longer. She is a fellow member of the hero clan, and the one charged with observing Mio. She claims that Mio will bring great disaster, but Basara proclaims that he will protect Mio as a girl on his own.