Here is the full list of all 52 Jerez's Arena achievements.
Ellin End
Claudia End
Bad End
Lose All Battles
Cleared Conqueror Mode.
Defeated Isekai Adventurer Lica in Conqueror Mode.
Defeated Glenn at the height of his power in Conqueror Mode.
True End
Reach any Ending
Win Ellin's third battle
Watched Ellin dance
Fed the birds with Claudia
Win Claudia's third battle
Claudia completed her 20th Prostitution Quest
Win Ellin's second battle
Completed Claudia's Oiran Request
Punished Ellin for stealing
Win Claudia's second battle
Ellin completed her 30th Training
Saved Ellin at the Tavern
Accumulate 100000 G worth of wealth
Stopped the Noble from bullying Claudia
Ellin completed her 30th Conditioning
Win Ellin's first battle
"Seduction" reached 200!
"Technique" reached 200!
"Lewdness" reached 200!
Completed the Undercover Mansion Mission
Ellin completed her first Mercenary Commission
"Obedience" reached 200!
"Kinkiness" reached 200!
Ellin completed her first Prostitution Quest
"Dexterity" reached 200!
"Strength" reached 200!
"Agility" reached 200!
"Stamina" reached 200!
Ellin completed her first Training
Ellin completed her first "training" Conditioning
Ellin joined the team!
"Willpower" reached 200!
Win Claudia's first battle
Claudia completed her 30th Training
Completed the Bandit Mission
Claudia completed her 30th Conditioning
Claudia completed her first Conditioning
Claudia completed her first Prostitution Quest
Claudia completed her first Mercenary Commission
Claudia completed her first Training
Claudia completed her 20th Mercenary Commission
Ellin completed her 20th Prostitution Quest
Ellin completed her 20th Mercenary Commission
Earned All Achievements