She followed Hal to a large building that faced the front street.
　As Filia rolled her eyes at the largest building she'd ever seen, Hal followed the wall that led to the side of the building down a small alleyway.

'Wait,'

　Without turning around to hear Filia's voice calling out to him, Hal went on ahead by himself.
　I had no choice but to follow him, and soon we were out at what looked like the back gate of the building.

''We're going out through there: ......

　Hal murmured in a weak voice while looking at the gate where the two guards stood in the distance.
　It didn't need to be said 'what it is' that they were leaving.
　It would be the people who were sold as merchandise being put on wagons to be taken to their buyers.

'Is Hal's sister among them?'

　Hal nods coyly to Filia, who asks to confirm.

　If you look at the building again, you will be overwhelmed by its size.
　We have walked a good distance along the wall from the main street, but even that distance is only a small part of the entire site.

　The wall is well over three meters high.
　I'm sure you'll be able to find a lot more information on this in the article.
　If what Hal says is true, that's where his sister is being held captive.

''How do you plan to infiltrate it?

　Filia tensed up at Rona's question.
　Because that tone of voice that sounded gentle (kowairo) was the same as that of Rona's when she instructed Filia and the other twins.

'There doesn't seem to be any magic-based tricks, and I think it would be easy to just get in: ......

　Although not as much as Aldis and Nere, Filia can also feel the magic power.
　Kirill begged me to teach him the trick, but this is only a sensory experience, and Filia can't put it into words well either.
　In fact, the fact that Filia couldn't feel the magic was more strange to her.
　The distance that Filia can search for magic power is about fifty meters, which is short compared to Aldis, but if she is careful to avoid a place with good visibility, she won't be easily found.

　Filia turns her gaze from the gate to the wall.
　She doesn't feel any magic in the wall or its surroundings.
　It's proof that there is no magic or sorcery to detect intrusion, let alone a barrier to physically prevent intruders.

　Even if it's impossible to pass through a gate with guards, you can still get past the wall if you choose a secluded place.
　If you build a foothold with magic, a wall three meters high is meaningless, and if you know where Hal's sister is being held captive, it's not impossible to rescue her.

''Specifically?''

'If we build scaffolding we can get over the wall, right? Then if we can extend the light, we'll be invisible, and if we're careful not to make any noise, I think we can go around the building without being detected. ......?

　When she said that to herself, Filia waited for Rona's reaction like a child being sentenced to a grade.

''Hmm, well, that's fine.''

　Inwardly, Filia was relieved to hear that it seemed to be a passing grade.

It's a good thing that you're not the only one who can do this. I'll only do my own.

Yeah, okay.

　As she replied, Filia pulled Hal's hand away from where she could see the gate and chose a secluded spot as she returned the way she came a bit along the wall.
　After looking around, and at the same time confirming that there was no human magic power, she began to form a foothold of magic power in the form of a staircase towards the wall.
　I lightly sprinkle the sand under my feet so that even Hal, who can't see the magic power, can see it, and a vaguely improvised staircase appears in the empty space.

''Huh?''

Be careful not to fall down the stairs, okay?

　Pulling Hal's hand away from his sudden surprise, Filia made her way up the stairs to the top of the wall.
　When she reached the top of the wall, she made her way down the stairs, this time in the same manner, and pulled Hal's hand down.
　He quickly obliterated the useless scaffolding and took cover in the shadows nearby for the time being.

'I'll make sure you won't be seen now. Don't let go of my hand so we don't get separated.

　I tell Hal a few words and he uses his magic again.
　Nere says that the reason why the human figure is reflected in the eyes is because a wave called light is transmitted through space.
　He says that if you force that wave to be longer, the changed light will no longer be visible to the human eye.

　In fact, Nere used this theory to make him disappear.
　Then it must be just as Nere said.
　Kirill had his head in his hands when he heard that story, but Filia could only think, "That's just the way it is.

　But as expected, she couldn't do it as well as Nere did.
　It's not enough to just stop being reflected in people's eyes, she says, it's finally complete when you get to the point of creating a disguised light to make it reach the other person's eyes.

'If you walk away, even though you've disappeared, you'll hear footsteps. You can't get rid of your scent. You can't erase the scent, much less the smell. Don't forget that.

　Remembering Nayle's words of warning, Hal exclaimed in surprise as he gripped his clasped hands tightly.

'Wow, I can't see ....... Your sister was a sorcerer, wasn't she?

Huh?

　For a moment, I didn't know what she was talking about, and then a dumb voice came out of Filia's mouth.

'Because this is magic, right?　Since you can do magic, aren't you a sorcerer?

'Yeah, is that right: ......?'

　Filia, who had never thought of herself as a sorcerer, tilted her head, but there was no one here to see it.

'If you're going to disappear, shouldn't you have done it before you crossed the wall?

But I thought that would be too dangerous to climb up the scaffolding: ......

'I made the scaffolding visible to the boy, and I think he would have been fine if he'd just backed off?　It's the risk of being found out that's a much bigger problem.

'Yeah, oh ....... Yeah, yeah, maybe .......

　Filia is depressed at Rona's point.

'Oh well. Anyway, there's no point in hiding here all the time, so let's get moving, shall we?

Uh-huh. Yeah.

　After regaining her composure, Filia gave Hal a few cautions and then looked around.
　A few human-sized magic powers could be seen in the nearest building, but these would not be captive humans.
　This is because, according to Hal, there are more than one or two refugees kidnapped by the Chamber of Commerce, and the Chamber of Commerce has no reason to let the captured humans act freely.

I'm going to pick a place with few people and walk around in circles to explore the magic. Perhaps Hal's sisters are gathered in one place.

　If there was a concentration of people who weren't moving around in one place, that was probably where the trapped refugees would be confined.

　It reminded Filia of the time when she and her fellow refugees had been monobites.
　They wore rings on their hands and feet and were not allowed to move around, and could only huddle with Liana in the wagon.
　I shake my head to force the anxiety that threatens to grab my heart at the moment and erase the abominable memory.

'Then, Hal-kun. Keep a firm grip on your hand so you never let go.

Yes.

　After confirming Hal's reply, Filia stepped out of the shadows and began to walk carefully so as not to make any noise.
　We approached the two relatively small buildings first, weaving our way through the shadows to check them out.

　The first building we approached seemed to be used as a storage area, and was frequented by people carrying bags and baskets.
　There are no windows that allow you to look inside until about two meters above the ground.
　That's why you can't see what's going on inside, but you can use your magical powers to explore it.
　Filia judges this building to be 'hazed' because there are no people staying in one place together.

''Is it that building over there?''

　Once again, Filia begins to walk cautiously with Hal's hand.
　The other small building seems to be almost empty of people.

　Like the previous building, there are no windows, and it is impossible to tell from the way people come and go what's going on inside.
　But when Filia explored the magic through the walls of the building, there was a reaction of about thirty people staying in one place in the basement of the building.

'Maybe here: ......'

　A large number of people who are not moving. And if they are not lined up in an orderly fashion, they are most likely to be captive refugees.

'We're going into the building, so be careful to make as little noise as possible.

Yes.

　After confirming Hal's reply, Filia stepped slowly into the building, pulling back her hand.
　Careful not to make any noise, she made her way down the dimly lit corridor, and soon she could see the door that was left open.
　Feeling my heart beat faster than usual, I looked into the room and saw three men sitting around a table, playing a card game.
　If I looked a little further, I could see the stairs that would lead to the basement at the back of the room.
　Considering the direction of the magical reactions that seemed to be the people being held captive, that staircase must be the place of confinement.

　Filia speaks in a whisper to Hal.
　Since the men's loud voices are echoing in the room, there is no worry that Filia's small voice will reach the other party.

'Maybe we can get to the basement from this room. I'll sneak through and go down the stairs. Make sure you never make a sound. I'm going slowly, so watch your step.

　Hal's grip on her hand was filled with strength.
　Taking it as a reply, Filia stepped cautiously into the room.

''Ah!　d*mn, you're losing again!

Hehehe. I'm sorry to let you win so much.

Next time!　I'll double the stakes!

　The three men who are engrossed in the card game don't seem to notice us.
　Feeling the sweat oozing down her back, Filia pulled Hal's hand and slipped past the men and down the stairs.
　Eventually, after descending the twenty or so steps, she breathed a sigh of relief.

'It's just up ahead, after all.'

　Down the stairs, several metal doors could be seen at either end of the short passage.
　The magical reaction could be felt from across one of those doors.

''Maybe it's here, right?''

Yeah. It looks like there are a lot of people in here for sure. But this door looks solid and of course it's locked. I suppose you could force it down with magic: ......

　If Rona is right and Filia can destroy the whole doorway, she should be able to do it.
　But now that we've infiltrated to avoid being detected by the other party, that's certainly not possible.

It's a good idea to make sure you don't make a sound ....... Yeah, I'll give it a try.

　Filia focused her attention on a part of the door, raising its temperature.

''Oh, okay,''

　He mumbles to no one and now extends his range to the entire door.

　Move.
　Move.
　Move.

　As I reminded myself of this, the small grains that make up the metal were released from their bonds through the medium of magic.
　That movement gradually began to change as heat.
　The door, which at first only emitted a faint warmth, gradually turned into a heat-releasing mass, and eventually transformed into a burning mud that melted down.

　When the door, which has been turned into a dull liquid, abandons its role, Filia and the others are able to see the scene inside that had been blocked from their view.
　In a room without any furniture, dozens of women with a dirty cloth wrapped around their bodies showed surprise and fear in their eyes.

'Filia. It was only the key that needed to be melted. If we melted the entire door, the heat would destroy everyone inside. Also, if the heat travels all the way to the top of the stairs, the guys from earlier will know we're there.

'Oh, ....... Gee, I'm sorry.

You'll be fine this time because I turned the temperature down inside. You'll be more careful next time.

Yes. ......

　Filia is depressed when she is taught that she almost harmed the person she was trying to save.
　Shuffling, she quickly cools and hardens the viscosity of the 'former' door.

'Wha, what......?'

　There were cries of confusion from some of the women in the room.
　It was only natural.
　Now that Filia and the others had disappeared, for them, the door suddenly melted down and they could hear people talking out of nowhere. No wonder they were confused.

''Oh, um. We're here to help. ......

　As Filia and her friends emerge after breaking the spell of concealment, the captive women begin to buzz with surprise.

'Girls ......?'

Are you here to help me?

Are we gonna be okay?

...... Hal?

　A voice called out Hal's name, mixed in with the many words of anxiety and relief, doubt and clarity that intersected.

'Sis!'

　Hal let go of Filia's hand, which had been held tightly until then, and ran up to one of the women.
　The woman, who appears to be slightly older than Filia, is probably Hal's sister.
　The woman's arms firmly embrace her brother's body as she catches Hal's jumping body.
　Filia's cheeks naturally relaxed at the sight.

　But this didn't solve everything.
　Rather, what follows is more difficult.

"Hey, Rona. They noticed--what's wrong?

　As she called out for advice, Filia noticed Rona turning her attention in the direction of the day after tomorrow.

'...... Oh, it's nothing,'

　Rona turned to face Filia and muttered to herself, "I wonder if it's just a coincidence.
　I'm not sure what Filia is talking about, but at that moment she tilted her head.
　Suddenly the sound of a deafening flute echoed in the room.

What?

　As Filia turned around in a hurry, she saw the reflection of a dark-skinned woman.
　A small thumb-sized flute was held in her mouth from where she had taken it from.