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