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