Hades himself owns a beast; guard dog named Cerberus. And I am sure The Underworld contains many countless unusual beings.
hades
Yes... beasts, monsters, and the undead
A three headed hound named Cerberus.
The Titans? Like, Kronos (Zeus, Posiedon, and Hades dad)?
Hellhounds, Medusa, and Hades (technically, he is not a monster, he is a god)
A dorky kid who turns out to be the powerful son of Hades
Zeus, Hades, and Poseidon, or the Big Three, swore on the River Styx, to no longer have demigod children, so when Zeus had Thalia, he broke his promise. Hades, angered that he broke his promise, sent horrible monsters after her.
There are many statues of Hades.
The Underworld, where Persephone is Queen, is the House of Hades - where the dead souls dwell, and where monsters abide.
Argolis and Elis had temples to Hades: there were many locations where Hades was worshiped.
Hades' Daughter has 621 pages.
Persephone, being Queen of the Underworld, dwells where Islands of the Blessed (where the heroes dwell after death) and Elysian paradise is - she also lives where such monsters as Cerberus guard the gates/house of Hades, and other monsters dwell.