A murder of crows.

A pride of lions.

A coven of witches.

Having originated in hunting terminology, such nomina collectivitatis are known technically as “venereal terms.”

So what's the venereal term for a group of warlocks?

The Warlocks of the Driftless have bruited a number of possibilities.

Dark: a clot of warlocks. (Warlock-magic not infrequently involves blood.)

Eerie: a quantum of warlocks.

Erotic: a tumescence of warlocks. (Warlockry being quintessentially men's magic.)

While it never hurts to consider new possibilities, in fact (as so often), Received Tradition provides an answer to the question: a coven of warlocks.

As with the phrase a coven of witches, a coven of warlocks uses the word coven not in its technical modern (!) sense of “a small group of specific witches/warlocks who meet regularly for worship and magic-making,” but in its older, more general sense of “a collectivity.”

This, of course, makes good sense.

For we are the male of the species, the Witch-Men, and together we constitute covens.