Romulus (no real name known) and his brother Remis are Exemplar 4s and some grade of Esper. They're members of the Goths and Bloodworm's "Cult of Cthul".
They have a run-in with Phase.
They take part in Bloodworm's attempt to sacrifice Sara.
Romulus talks Screech out of committing suicide after the sacrifice debacle.
The have a one line appearance in the fight with the Syndicate goons at the Halloween dance,, and a brief reference on Parents' Day.