Here is the full list of all 54 Yorna: Monster Girl's Secret achievements.
Beat Leary.
Beat Gabby.
Beat Calista.
Beat Ayane.
Beat Idris.
Beat Succubus.
Beat Agni.
Beat Serena.
Beat Desona.
Beat Lizzy.
Beat Felicia.
Beat the doppler.
Beat Yorna.
Ruffle up Hanako.
Beat Sarana.
Complete Vagabond's quest line.
Complete Octa church's quest line.
Complete shrine maidens' quest line.
Dominate an ogre.
Dominate a nereid.
Dominate a gnoll.
Dominate a minotaur.
Dominate a tentagirl.
Dominate a moth.
Dominate a titania fairy.
Dominate a gargoyle.
Dominate a night gaunt.
Dominate a dark matter.
Win at the cards once.
Dig up a treasure.
Earn a private audience with the baron.
Dominate a jinko.
Reforge a sword of the past.
Win at the cards ten times.
Get the pure ending.
Get the neutral ending.
Get the lusty ending.
Try to outfox the fox.
Awaken a sentient weapon.
Earn 15th lewd level for Ada.
Dress up into Eve's costume.
Dig up all treasures.
Beat Kara.
Beat Zoja.
Beat Jaheera.
Beat Ife.
Beat True Yorna.
Dominate a pandarian.
Dominate a werewolf.
Dominate a catman.
Dominate a kejourou.
Dominate an akaname.
Dominate a chimera.
Dominate an anubis.