Here is the full list of all 29 Scarlet Maiden achievements.
Earned after 10th run
Completer the quest ‘It’s a Strap’
Complete the quest ‘Green Delight’
Level Roman to level 5
Level Faelina to level 5
Level Bruce to level 5
Defeat Queen Lily
Slay 200 enemies in one run
Complete the quest ‘Magic Flute’
Defeat the Grand Archivist
Slay 100 enemies in one run
Find 50 items in one run
Gain 100000 sin total
Level up to level 50
Complete the quest ‘Masquerade’
Gain 15000 sin in one run
Complete the quest ‘Steamy Contraptions’
Defeat the Earth Mother
Level up to level 10
Find 20 items in one run