13 With this vow, I will bring you down!

Unagi Hirokawa. 

It is a Michelin 1-star restaurant unagi (grilled eel) specialist restaurant located on the main street of Arashiyama.

As Mizuto had promised Yume to eat an eel after they finished their endeavor, he took her to this place. Sitting side by side, he looked at the menu and saw that the most expensive item was 13,000 yen, a set course menu. 

"I will take the E-Course menu and Yuzu soda." 

If it was before, he might hesitate, but now, with how fat his wallet was, there was no need to hesitate. 

"How about you, Yume?" 

"...Is it really okay?" 

Unlike Mizuto, who was confident, Yume was helpless when she saw the price of the items on the menu.

Mizuto rolled his eyes, then said to the waitress, "Also, get her E-course menu and orange juice." He knew it was hard for her to choose an item from the menu, especially with how expensive each item was. 

"E-Course is too much for me!" Yume couldn't help but remind Mizuto since she could see it had a lot of portions. 

Moreover, this course was too expensive! 

"It's okay. It's a special day. If you can't finish it, then I will help you to finish it," he said softly, telling her that everything was going to be okay. 

Yume pouted but didn't argue with him since she was also interested in the unagi since it was a rare chance for one to eat an unagi, especially with how expensive this dish was. 

Nevertheless, what had happened today made her see the different side of him. If it was before, would he do this? The previous Mizuto was like a sloth, only moving slightly, which was reading a book or buying a book at the bookstore, but now, he was so active that she was almost overwhelmed, especially since he could talk about such a large amount of money calmly with the shop manager before. It was like he had done it several times, full of experiences, which made her in a daze. She also had to admit that he was so attractive that she became so crazy about him that she wished to go home as soon as possible so she could do something that couldn't be shown in public. 

"Have you been there often?" Yume asked curiously. 

"No, that's my first time, or rather, it is my first time selling an antique." 

"Huh? Really?" Yume was surprised since Mizuto appeared so calm, and it was like he had visited that type of place so many times. 

Mizuto nodded, then looked at Yume with a smile. "To be honest, I didn't expect to find such precious items when I went out before, maybe because I am with you, so my luck is good." 

Yume blushed and chuckled at his joke, but then she shook her head and said sincerely, "No, this has nothing to do with me. It's all due to yourselves." The reason why he came to the flea market was due to his initiative, and the reason why he could find many precious antiques was due to his skill, too. She did not partake in it, so it was quite shameless if she really said that what he did was partly because of her. 

"..." 

Mizuto was silent and thought that this girl was really a good girl, which made him sigh. 

"Wh-What is it? Why are you looking at me like that?" Yume blushed, feeling quite excited by his calm gaze. 

"It feels weird to hear that from you." 

Hearing that, before the unagi came, Yume wished to swallow this guy whole for annoying her! 

Still, there was something that Yume wanted to ask. However, she was shy and wasn't sure how to talk about this problem with him. Moreover, why did he not say anything about that?! 

"What's wrong? The toilet is over there." 

"I don't want to go to the toilet!" Yume puffed her cheeks angrily like a puffer fish. 

Mizuto couldn't help but poke her soft, stuffy cheek with his finger, causing her to blush shyly, then swept his hand away. 

"I am talking about something serious! Listen to me!" 

"Okay, okay. I am listening. What do you want to talk about?" 

Watching him patiently, waiting for her to talk, Yume sorted out her emotions, and she also became shy. Still, he didn't hurry her and let her talk slowly. 

"On-On that shop earlier, you told them that we-we were dating..." 

She was so nervous, and her words stuttered, but even so, she was able to finish what she wanted to say even if, in the end, she ended them with a mutter that was almost impossible to hear. 

However, after Mizuto rose to his level, he could feel that his physical ability became stronger, his senses were sharper, and his brain became clearer. Still, this improvement wasn't much, and it was only noticeable when he rose his level from one to ten, so of course, he heard all of Yume's words clearly. 

Still, he didn't want to define their current relationship; an ambiguous relationship was the best for them currently, especially with their current relationship as siblings. Moreover, the word "stepsibling" was more interesting than "girlfriend," right?

"If I didn't do that, I wouldn't be able to sell the antique." 

"Huh? What do you mean?" Yume was startled. 

"That place is a government-license appraisal shop. It has strict rules, and one of those rules is that they are unable to buy something from a minor." 

"Wh-What?! Then...?" 

"What I am doing is illegal." 

"...." 

"But you don't need to worry. It's going to be okay." 

"Huh? Really? Why?" 

Yume, who felt her heart beating so fast and full of fear, somehow felt at ease when she saw how calm Mizuto was, and at the same time, she thought that she had just done something as significant as robbing the vault of Mitsubishi UFJ Financial Group. 

"Because he had accepted the good, and he paid me. Moreover, he didn't realize that I was a minor. Lastly, as the transaction has concluded, he was also partly at fault since he didn't realize that I am a minor." Mizuto then looked at Yume and said, "This type of industry is quite strict, especially when there are many fakes, robbers, and many others in the industry. If one wants to enter this industry, they have to be careful, especially when the source of the antique is often questionable since many of them get them from a criminal." 

Yume only realized that this antique industry wasn't as simple as it seemed, but the more dangerous it was, the more curious she was, especially when Mizuto always had calm and didn't even have a cold sweat. He had always exuded this vibe that told the people around them that everything was going to be okay. 

Was this because of his handsome appearance?

This was probably the biggest reason. 

However, this mysterious yet confident aura exuded on his body. 

Somehow, Yume could imagine that Professor Moriarty was made in front of her eyes. As he made his decision coldly, logically, without a single feeling like a machine, when he finished his crime, he would come to her, and then he would show the desire that he had been keeping inside, unleashing them on her, as she could only cry under him. Yet, even if he treated her that way, she was the only one he cared about, which somehow made her breathe rapidly. 

"...stop thinking about something dirty in public." 

"I-I am not!" 

However, her voice was shaky, clearly showing guilt, but then she quickly asked, "But why can't a minor sell an antique?" She tried to change the topic of conversation so he wouldn't tease her anymore. 

However, Mizuto also didn't open this facade and answered her question, "It's because those business owners are afraid of the source of the antiques from the minor." 

"What do you mean?" 

"Let's say that a minor came to your shop and brought a precious antique, wishing to sell it to you. So, when it happens, where do you think this precious antique comes from?" 

"...their parents." Yume quickly understood everything. 

"That's right." Mizuto nodded. "They will think that the minor stole the antique from their parents. That's why they won't buy an antique from a minor." 

"Then-then, why did you tell them that we're dating? What did it have to do with this matter?" Yume asked with a blush on her face. 

"That way, it will make me appear more mature. Frankly, I was thinking of telling them that you were my wife or fiancee." 

"Wh-Why didn't you say that?" Yume asked, as she imagined she was in a white dress with him by her side, which made her blush and show a silly laugh. 

"...because we don't have a ring." 

While he was speechless by Yume's reaction, he answered her question. "As for whether I didn't say that we were a stepsibling or a friend, I could only say that that identity is troublesome as it might lead that manager to question us." 

"That's why you said that we were a couple?" 

"Yes, that's why." 

Yume pouted, feeling that she was being played, but—

"Or do you want it to be real?" 

A hot, gentle, and low voice invaded deep into her semicircular canals. 

When she turned, he was beside her with his gentle yet manly eyes staring at her firmly. 

Only—

"Um, guess your order is here." 

"Thank you. Please put them here." 

"....." 

Yume took a deep breath, trying to calm herself, and swore to herself that she wasn't angry. 

"Come on. Let's eat. It won't be good if you eat it when it is cold." 

"....." 

Watching how casually he was to make her feel horny and then throwing her away again, Yume felt like she was really a good girl not to beat this guy up, so at this moment, she made her determination!

'I will make you confess to me!' 

Otherwise, this heart of hers wouldn't be satisfied!

As she chomped down on the delicious unagi with her chopsticks, she made this vow!