In their upcoming battle against Supernova, Kain and the others were surprised by the profile of one first-year that looked suspiciously like Alexei and Dmitri, aside from his dark red hair. In particular, all three of them have the same identical red eyes—Nikolai Sanguine.
Like Dmitri and Nikolai he is form the Sanguine family and, like pretty much everyone else in that family, someone with an attribute related to blood-type spiritual creatures.
Kain and the others would probably be interrogating their seniors for information about this cousin, if each year level were not separated for targeted debriefings since each of them has a different school as their opponent and their performances are now evaluated separately.