Just finish the game once and this will unlock it. It's not a scene just the complete collection of all dresses.
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And I have another question, where do I get the swords that I can enchant from the guy in the laboratory? Like the comrade or other the others.. I went to all of the weapon shops, but still didn't find them, do I need to craft it? Maybe in the next updates you can make a book or something that tells players how to get them.
And also... How do I find Yorna again so I can make the slutty sex scene? And the mansion gang bang.. I can't get the normal one, only the slutty one, I tried like minimum of 50 times, changing the clothes still doesn't do anything, I only need these two scenes to make the full gallery. Oh.. I didn't mentioned I have slutiness level 70, I tried drinking potions so I can walk nude.. Is this the problem?
You get parts of these swords from puzzles during the first half of the game then Ada will comment on restoring the blade at the blacksmith. Then you need to enchant it inside the castle’s lab and choose blade’s stats.
You don’t need to fight bosses twice to get both scenes. From day 1, each boss gives you a special heart item. Use it to unlock both scenes with the corresponding in the gallery.
The type of scene depends on Ada’s lewd level. After a certain threshold, you‘ll get only lewd ones. Decrease Ada’s lewd level or make a pure playthrough to get the normal ones.