Which disloyal goatherd helps Penelope's suitors in The Odyssey?

The disloyal goatherd who helps Penelope’s suitors in The Odyssey is Melanthius.

Melanthius is an enslaved goatherd belonging to Odysseus’s household. Unlike the loyal swineherd Eumaeus and cowherd Philoetius, he sides with the suitors who occupy Odysseus’s palace during the king’s twenty-year absence.

He provides the suitors with the best goats, serves them food and wine, and insults Odysseus when the returning king is disguised as a beggar. His betrayal becomes especially important during the palace battle: Melanthius attempts to take weapons from the storeroom and arm the suitors, but Eumaeus and Philoetius catch and bind him.

Readers often confuse Melanthius with his sister Melantho, a disloyal palace maid who is associated with Eurymachus. Dolius is their father, while Eumaeus and Philoetius remain loyal to Odysseus.