So......achievements just got added to this game.
How to get them? I'll try to make this really short.

*Chronologically, this is my very first Steam guide that I published,
I hope you readers find it easy to read and useful =D

A normal run reading the entire story should unlock these achievements:
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Usually one achievement after the end of each chapter;
in case the acheivement icons doesn't make it obvious enough.


Oats and Curry achievement should pop up after you finish reading the story.

*If you've already read the entire Fault Milestone before the implementation of the achievements,
just holding down the LeftCtrl button to skip through the entire thing works as well in getting those acheivements, since there isn't a minimum time criteria.

It says clear in both English & in Japanese, yes, though I interpreted it literally and it works as well.

Here's what I did to get the acheivement.
1) Clear the game in English, and have the relevant save files.
2) At the main menu, change language to Japanese.
3) Start the game in Japanese.
4) Open up the save menu and load from the save that's closest to the ending.
5) Play till the end.
6) Aeroratum achievement should pop up.

If for some reason that doesn't work, here's what others have tried for getting Aeroratum
1) You need to load a save near the end THEN switch language to Japanese.
2) Or start the game in Japanese and hold down ctrl to fast forward through everything.

Well, this is an interesting one.
-- Replayed Selphine's and Ritona's change scene over 50 times --
*This scene is in Chapter Two.

Instead of (save before scene + play scene + reload before scene) x50,
just using your mouse wheel to scroll back & forth between the start & end of the scene x50 works fine too.

TLDR, I quote another user's comment;

it is from the start of the CG until the background change in the shop

If just words are a bit to vague for you, here, do the necessary with this particular scene.

The picture on the left will be your starting point;
(not too far off after the dinner event at the tavern)

The key word here is "tailor new clothes",
CG transition is just a few clicks away.
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This picture will be your ending point.

Once you reach this scene, repeat the transition 50 times.

--Watched child Rune stab Marco's art in the gallery for over 2 consecutive hours in awe --
*Apparently, this one is really time sensitive because of the term "2 CONSECUTIVE hours".
People have commented that minimizing the game window or opening Steam interface seems to reset the time.

A shortcut has been found if you really prefer doing something else in those 2 hours.
1) When you first play the scene from the art gallery, take note of your computer's time.
2) Set it to a later time, slightly less than 2 hours. (eg 1 hour & 57 to 59 minutes later)
3) Let the Fault Milestone One window be active on Sociopath Rune art for a few more minutes.
4) Acheivement should pop up. *I tested this myself & it works*

A Steam user has mentioned that switching to Windowed mode but not minimizing it works just fine to get this achievement too

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Again, if words aren't helpful;
first go to the gallery and look for this image.
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Now choose this picture.

Whether you choose to have a continuous 2 hour staring contest with Rune or *ahem* use a shortcut, I'll leave that entirely up to your choice.