Alipheese the 16th (Hades) is one of the Monster Lords, who appears in Monster Girl Quest: Paradox.
Whether or not this is the same Alice from the original franchise is unknown.
Talking to her in battle results in her making remarks about what could have been or how Luka's decision made her realise what humans are like. She is most likely from a universe where Luka chose to be baptised first instead of helping Alice in part 1 of the original franchise.
How to Fight
Alipheese the 16th can be encountered in Hades by choosing to challenge Reaper to a fight. Beating Alice once after asking to fight Reaper will make her available to fight like the rest of the bosses in Hades.
"A mysterious monster only matched by her mysterious power. With her identity unknown, it's unsure if there are even any monsters who can match her strength. Though it appears she means no harm to humans, she is merciless if one dares to challenge her. The price for challenging her is pricey, indeed."
- Attack - One Foe, Normal Attack
- Monster Lord's Cruelty - All Foes, Auto-Hit, Dark Attribute, Ignore Def, Death 10%
- Omega Blaze - All Foes, Magical, Fire Attribute, Burn 10%
- Sigma Frost - All Foes, Magical, Ice Attribute, Freeze 10%
- Demon Eyes of Seduction - All Foes, Seduction 75%
- Tail Bind - One Foe(Luka), Pleasure Attribute, Bind(3 Turns Break)
- Pleasure Drain - Rape, Drains HP
- Demonic Pressure (M) - One Foe(Struggling Luka), Physical
- Demonic Pressure (F) - One Foe, Physical, Bind 50%
Beating her can either be very easy or very hard. You should be at least level 25 and be capable of taking on one of the Angels in Iliasville (Alt). If you have done this, just fight her like you would any boss. Use evasion increasing skills like Sky Dance (from the Wind Harpy) to avoid most of her attacks.
Her only attack that might give you trouble is Monster Lord's Cruelty due to it hitting automatically and multiple times. But if you're evading most of her other attacks, you should be able to survive it.