Story-related Achievements
These are self-explanatory and cannot be missed.
Instructions! Instructions! Instructions!
Finish the tutorial.
Once Upon a Time
Finish the first chapter.
The human MageDoll
Defeat Pinocchio in Story Mode.
And they lived happily ever after?
Finish the story mode on normal difficulty.
Grimoire of Knowledge
Watch the credits until the end.
Gold-related Achievements
You will need to buy around 60-70% of the items in each category to unlock these achievements. Since outfits, lingerie and accessories can improve your performances in battle, it is recommended to unlock outfits and lingerie first, then accessories, and hair sytles at last. If you are short on gold, hard story stages 7 and 10 are good for farming, respectively providing about 1000 and 1100 gold (there are two extra piles of gold coins on higher ground in stage 10).
Let down your Hair
Unlock a certain amount of hair styles.
Long Live Underwear
Unlock a certain amount of lingerie.
A Princess' Wardrobe
Unlock a certain amount of outfits.
I'm ready for everything!
Unlock a certain amount of accessories.
Enemy-count Achievements
For getting these achievements, you need to defeat 10000 enemies in total, which is of course a large amount. By the time when you have finished the story modes in both difficulties and all the challanges, it would count up to about 6000-7000. After that you will have grind the rest in Defeat All Enemies stage in challange mode. Personally I recommend the stage for LV.21-30, in which the enemies are female warrior with axes and tend to engage you in melee combat, so that you can simply kill one group by a sliding tackle. At level 50 with full upgrades, each run of 200 kills takes only about 80 seconds.
100 at One Blow
Defeat 100 enemies.
1000 at One Blow
Defeat 1000 enemies.
10000 at One Blow
Defeat 10000 enemies.
Stun-related Achievements
You will definitely need to stun boss enemies in order to defeat them. I got the 100th stun when beating the last challange against Pinnochio.
The stun judgement in this game is quite loose and comfortable, and you can even release and press the defense button again during enemy attacks for the stun to effect.
10 Years of Deep Sleep
Stun 10 enemies.
50 Years of Deep Sleep
Stun 50 enemies.
100 Years of Deep Sleep
Stun 100 enemies.
Combo-related Achievements
It is easier than it sounds. In challange Defeat All Enemies LV.41-50, you will face 20 high level enemies at the same time, and you can keep hitting enemy corpses without breaking your combo.
100 Steps to Success
Get a 100-Kicks-Combo.
500 Steps to Success
Get a 500-Kicks-Combo.
1000 Steps to Success
Get a 1000-Kicks-Combo.
Challenge Achievements
Enjoy your imprisonment
Finish the story mode on hard difficulty.
You may need some grinding and farming at the beginning of hard mode. Personally, I did it on stage 3 in hard difficulty.
Cinderella the Legendary Fighter
Finish all challenges.
I think the only difficult challenge is challange for Lv.50, where each encounter includes 3 heavy soldiers and about 10 red-hair female axe wielders, and the last encounter additionally includes Robot as a boss. I suggest you beat only one encounter for filling up your special attack gauge, and then aiming directly for the last encounter, passing by all the others. In the last fight, use one or more special attacks at once to clear out all the enemies other than Robot and deal with him in a solo combat.
Melting Snow
Defeat Snow White in Story Mode Chapter 12.
True Love's Kiss
Defeat Robert in Story Mode.
It is highly recommended that you do these two battles in normal story mode after your level and attack are capped, otherwise your damage may not be sufficient to defeat Robert in time.