The seven deadly sins in Latin I guess?

Oh wow even the bosses are related to those sins:

Associations with demons
Lucifer: Pride (superbia)
Mammon: Greed (avaritia)
Asmodeus: Lust (luxuria)
Leviathan: Envy (invidia)
Beelzebub: Gluttony (gula or gullia)
Satan: Wrath (ira)
Belphegor: Sloth (acedia)

So it's not related to Mona hm.

Asmodeus: Lust
Azazel: Vanity
Bael: Gluttony
Shadow Futaba: Sloth
Cognitive Wakaba Isshiki: Wrath
Mammon: Greed
Leviathan: Envy
Samael: Pride
The prison in the abyss of Mementos: Apathy (Acedia or "Spiritual Sloth")
Yaldabaoth and Satanael: All the Deadly Sins

That stuff being related to Mona is probably a very spoilerish thing.

Maybe.
He does lust after Ann the entire game.