On the 2nd of January 2097 AD, the 10 Master Clans and 18 assistant houses received a letter each from one of the leaders of 10 master clans, Yotsuba Maya. Its contents informed them about the new clan leader, and unexpectedly their commitment to marriage. Shiba Miyuki will succeed Yotsuba Maya as the clan leader, and Shiba Tatsuya will be her fiancée. This will cause a stir in the world of magic in Japan.
That afternoon, Ichijou Masaki is summoned by his father Ichijou Gouki. They engage in a conversation where Gouki asks Masaki if he likes Shiba Miyuki. After repeatedly asking Masaki, Masaki confesses that he does and it all started at the 9 Schools Competition including their dance on the final night of the competition. He the proceeds to ask his father what this is about. Gouki informs him that, 30 minutes ago he received a message from the Yotsuba family. Masaki is not surprised as this not uncommon. However Gouki has more to say. Gouki tells Masaki that the Yotsuba family had a meeting and elected Shiba Miyuki as the new clan leader. Hearing this causes some commotion with in Masaki. This commotion goes out of control when Gouki informs that Shiba Miyuki is to marry her cousin Shiba Tatsuya.
Masaki says this is impossible because they are siblings. However Gouki has reviewed the information provided and Tatsuya’s changed status is due to the fact that he is the son of Yotsuba Maya. He was born from one of her cryopreserved eggs. Masaki suspects this is a lie and Gouki has his doubts too, however this decision lies with the Yotsuba. It does not matter if they are siblings or cousins, the alarming thing is that as magicians of Japan they are obliged to leave behind descendants and improve the quality of magicians’ thorough marriage. However by doing this, the Yotsuba are completely ignoring this premises. Therefore it is important to know how Masaki feels about Miyuki. Since Masaki likes her, Gouki decides to do something about this. Masaki does not have to worry, Akane his sister, will be the next leader of the Ichijou Clan so he would not have to worry about any commitments later.
Seagusa Koichi had suspected that Miyuki was part of the Yotsuba clan due to her enormous magic power, Inferno and Niflhiem. Also the Yokohama Incident and her strange power to exterminate others (Cocytus). He also primarily suspected Tatsuya for his extraordinary engineering skills during the 9 Schools Competition. Later investigations also revealed his power to alter information linking it to the phenomena seen during Scorched Halloween. He also knew of his relationship with Magic Battalion 101. From these he knew Miyuki and Tatsuya must definitely be part of the core members of the Yotsuba. But he did not know they were cousins and are now engaged, confirming the fears of Kudou Retsu. This had altered the power balance further, and it was now too late to do something. Maya had played the first card and ended any possibility of Interference by choosing to make a public and official announcement to the Magic Association, the 10 Master Clans and the 18 numbered families. This is why all the other families sent messages of congratulations. However the Ichijou family made a formal complaint possibly creating an opportunity to change things.
Koichi then calls for Izumi, Kasumi and Mayumi. They greet him, and asks him why he summoned them. They have still have not heard the news. He proceeds to tells them that a he received a letter from the Yotsuba, drawing Mayumi’s attention. He then reveals that Yotsuba Maya has selected Shiba Miyuki to be the next clan leader. This news causes a reaction from the three. Mayumi was suspicious that the siblings belonged to the extra from the ancestors of whom were bearing the number four in their name; therefore the news took her by surprise. When Koichi announced Miyuki and Tatsuya are engaged, a greater reaction is caused by the three. Koichi then goes on to say Miyuki and Tatsuya are cousins, not siblings and that Maya announced that Tatsuya is her son. This shock Mayumi. Koichi then mentions the formal petition made by Ichijou Gouki and asks each of them what they think of Tatsuya.
They reply:
Mayumi: An excellent Kouhai, his sight wonders everywhere.
Kasumi: A formidable senpai, even though she cannot explain why but she can sense that he has formidable power.
Izumi: Due to focusing on student council work, she cannot say much.
However Koichi insists to know Izumi’s opinion, so in the end Izumi says that Tatsuya has immeasurable power. She goes on to explain how Tatsuya was the key man at the 9 Schools Competition. His implementation of flight magic at Mirage Bat and the improved versions of Phonon Maser and Invisible Bullet this past year was key to their achievements. However the way you see the world is fundamentally different to how others see it. During this Mayumi is looking away and appearing restless. Koichi then proceeds to ask Mayumi what she thought of Tatsuya as someone of the opposite sex. Mayumi is speechless and does not know what to say. Koichi goes on to say that there will be no problem if Mayumi decides to becomes part of the Yotsuba if the Yotsuba are willing. Especially since there is only an age difference of two between them. After hearing this Kasumi and Izumi strongly protests against this idea. This is because the announcement of the engagement was formal and Tatsuya and Miyuki are seen as a couple in the eye of the public. Mayumi approaching Tatsuya will not only ruin Miyuki’s reputation but Mayumi will be seen as shameless women with a seducing manner. Izumi and Kasumi also agree that the engagement must have been approved by Miyuki. Koichi then realises that the situation is more delicate than he had previously thought. He then leaves them to think for themselves.
Koichi receives a call from Ichijou Gouki. Koichi understands from the discussion with his daughters that the Gouki’s call is not only for political reasons but also fatherly reasons. Gouki goes on to say that the engagement is not wrong. However Miyuki is an exceptional mage, and the engagement between Tatsuya and Miyuki will be a massive loss to the world of Magic (he is referring to descendants). Like Miyuki he thinks of Tatsuya as an incredible mage. Gouki admits that Tatsuya winning against Masaki in the 9 Schools Competition was no luck. Masaki was leading 3rd high to victory, however Tatsuya gave First high the advantage and gave them 1st place against all odds. Koichi then says that he would like to have Tatsuya as his son, and that Mayumi did not reject him when Koichi asked about him becoming her husband. Gouki then asks about the commitment to Itsuwa, Koichi then replies that its not final and how Hirofumi and Mayumi are not really interested in each other. Also Mayumi will 20 soon.
Gouki then mentions his formal complaint to the Magic Association. However at this point it is too late. Maya won’t change her mind. However he expects to get an opportunity where Masaki will be able to “woo” Miyuki. In the end Koichi and Gouki decides to work together to make Masaki and Mayumi woo Miyuki and Tatsuya, and make them change their minds about the engagement.
The story moves to Miyuki, Minami and Tatsuya. Due to recent events, Hayama arranged for them to move the Yotusba’s second residence in Tokyo to increase their safety. Tatsuya had to do some things before hand, however moving immediately is not a problem. They call a head and arrange a meeting with Kokonoe Yakumo. Upon arrival they had to wait 30 minutes due to an unexpected visitor. Once the visitor leaves, Tatsuya watches him from afar. He notices that the man is of old age and appears like a normal Buddhist monk, however he can feel great power within him. The visitor stops and returns Tatsuya’s gaze. Tatsuya senses something different about him. For some reason his gaze caused him some concern. While old man then turns around and carries on. Miyuki then calls Tatsuya out of his thoughts.
After wishing each other happy new year, Yakumo congratulates them on their engagement, saying that they even manage to deceive him. This causes Miyuki to blushes. Her face becomes tense when she tried to guess the meaning behind Yakumo’s words. Yakumo then proceeds to ask them what is the truth. Tatsuya simply tells Yakumo what he was told, however Yakumo has his suspicions. However Tatsuya proceeds to say that there is no way he can know the truth of something that happened so long ago. They leave the temple with Yakumo reminding Tatsuya that in the morning he will be taking part in stronger training. Their relationship stays the same despite what has happened, and Yakumo does not intend to hold anything against the siblings.
The next day Tatsuya goes to Independent Magic Equipped Battalion’s Headquarters. It is strange to see an officer dressed casually like him. After entering, he is received by the newly promoted Fujibayashi Kyouko. After exchanging greeting with Kyouko he is lead Kazama, who has been promoted to the general commander of the battalion instead of Saeki. Kazama goes on to say that promotion not only means financial reimbursement, but he can also stand up to his subordinates. Yanagi and Sanada has also been promoted. However their promotion took several months due to various complaints. However their achievements, especially in Yokohoma showed that they are a special force capable of turning over whelming situations. Kazama then asks Tatsuya if he can continue to count on his cooperation, especially since he has been publically recognised as the Yotsuba. Tatsuya says that he has no problems. (Note: Its only for the battalion, not for the defence forces). Due to Kazama the army cannot touch Tatsuya, even if Tatsuya is associated with the Yotsuba clan.
Kazama mentions that the “climate” has not been stable recently several wars have been sparked. Soon there will be conflict in east Asia and the world is approachi