Connal, Sirius, Bennet, Fern, Blake
What they did was straight up unforgivable
Let's start with Connal: he tortured and killed children in that twisted orphanage of his, what more to say?
Sirius is even worse: he burned down and tore apart the Belrose Manse, killed Charlotte, Saphira and Laura's parents. killed Eclipse, killed Heather's Mother and was prepared to kill everyone in the Fiore Mansion if not for Titania's Excadrill
Bennet is a creep
Fern's a jerk
and Blake's a bigger jerk