A/N: I got inspired writing this fic while listening to the new song of the K-pop group Seventeen. I didn't totally based it on the English Translation, but I really got inspired just listening to it and this is why I used 'Habit' as the title. This is mostly on Heine's point of view. Anyways, hope you liked it.

Heine's POV

She has visited the palace many times ever since I started tutoring the Princes. She is also welcomed by the two guards posted at the front gates. She was like the older sister figure of Prince Bruno, Prince Leonhard, Prince Licht and Princess Adele.

We have introduced each other one day. But, I was quite shocked to see Prince Kai having a very good conversation with her..... Since she was the only one who understands him the most.

"They've been childhood friends ever since father met one of his good ole' friend" Prince Licht said

"He once worked as the captain of the guards here. But once she was turning at the age of 13, he decided to drop his position as captain" Prince Bruno explained

"He was also a great Uncle to us back then. Now, only older sister (F/N) came to visit" Prince Leonhard commented. I then looked at the pair, Prince Kai was back-hugging her

"(F/N) looks tired"

"Really? But, I've been getting some good enough of rest"

"Rest, more"

"You know I can't just yet. His highness the King wanted to talk to me" this made me curious as to why Viktor wanted to talk to her

"Rest~"

"Kai, you know that your pouting face won't work..... or your sulking face. Sigh, alright. I will take some rest. After your lessons, I still need to see Princess Adele and your grandmother"

"Knowing Shadow, he is the one to take you to them" Prince Bruno told her as she giggled. The grandfather clock started to chime

"I better go and find them. Listen well to Professor Heine, okay Kai?" he nodded and she patted his head.

"I'll see you later, Kai. Oh, Leo, I'll tell one of the maids to prepare Sachertorte if you get a passing grade" Prince Leonhard suddenly engulf her in a hug

"Thank you!" she then patted his head as well. She then bowed to me and left the study room.

The afternoon came and one of the maids entered the study room as per request from me and (F/N), she delivered the Sachertorte for Prince Leonhard. Prince Kai then left as we finished and we heard the bark of Shadow

"It's that time already" I looked at Prince Licht

"Time?" I asked

"For Older Brother Kai and Older Sister to meet at the gardens" Prince Licht answered and ushered me to the window. Outside, we saw the both of them taking an afternoon stroll with Shadow

"Older Sister (F/N) looks different" Prince Bruno commented

"Because she's sad" Prince Licht said

"How could you know?" asked by Prince Leonhard who was still eating his Sachertorte. Prince Licht then grinned to the two Princes

"You know that I understand women more than you two" I looked back at the pair. Something might have happened during her talk with Viktor

Weeks had passed, she hasn't visited ever since her last. They were getting worried for her, mostly Prince Kai

"Older Brother Kai, did Older Sister (F/N) told you when she will visit again?" Prince Licht asked as Prince Kai entered the study room, but he shook his head. Prince Licht and Prince Leonhard both pouted and sat down on the sofa

"Did something happened to her?" Prince Bruno muttered. I looked at the Princes worriedly as they are getting worried for (F/N). We then heard a knock and the royal butler of the family entered

"Your highness, Princess Beatrix von Lothringe has arrived and is waiting your father's study and wishes to talk to Prince Kai" Prince Kai solemnly nodded and left the room

Days had passed and she hasn't come back, and we got the announcement that Prince Kai and their cousin Princess Beatrix will be we by the next month. His brother's congratulated him, but they know Prince Kai's feelings with (F/N). Princess Beatrix has been staying for quite some time and also joined us with the Princes tutoring.

Princess Beatrix had many attempts for Prince Kai to notice her. But, Prince Kai is still waiting for (F/N) to come back. All of the things he ever do, he stopped doing it and always heads to his room, locking himself in.

"I can't believe Older Sister (F/N) quit!" Prince Licht whined as he got back from his part-time job at Café Mitter Meyer.

"She even quit her part-time at the library" Prince Bruno commented

"She really is not going to communicate with us anymore, does she?" Prince Leonhard asked, but the three Princes took a glimpse at their second Prince.

"If you excuse me" they looked at me curiously as I left the and headed to Viktor's study room

"King Viktor" I then knocked at the door

"Come in" I then entered the room and closed the door behind me

"Ah, Heine. I wasn't expecting you to visit me at this time"

"This is kind of important" Viktor sighed

"Is this is about Kai, we don't need to talk about it" Viktor then continued his work

"But his already failing all the test that I gave him, he hasn't been focusing as well. Even though he has been practicing his communication skills, he is back to the way as he is before. I know that you're the reason for (F/N) to stop coming here at the palace as it might make a scandal regarding Prince Kai and her. But, you must understand his feelings towards her" I explained, but Viktor just released a deeper sigh

"I already know that. But, Princess Beatrix has been Kai's fiancée since they were kids. I just can't suddenly cancel their engagement"

"Do you care more about that? Or your own son's feelings?" he didn't answer. I also released a sigh as I left his study, not knowing that someone was eaves-dropping on our conversation

The next few days, I went to Café Mitter Meyer to watch over Prince Licht for his part-time job and for me to meet someone. She bell on top of the door chimed, signaling that they have a new customer.

"Ah! Older Sister!" Prince Licht exclaimed as he quickly rushed to (F/N) to hug her.

"I missed you so much, Older Sister!" Prince Licht started crying

"Oi, Richie! You're making a scene!" the owner scolded, Prince Licht just pouted

"Richie, you still have a job to do. Don't forget" she told him as she smiled sadly at him. She then turned to me as I nodded my head. She headed to where I was seated and sat in front of me

"Is there something important you need to tell me?" she asked as one of the waiter gave her a cup of water

"It's about Prince Kai" her eyes got wide, but suddenly turned to disappointment

"It is not deemed important, Professor Heine" I took a sip of my drink

"You truly love him, don't you?" I asked straight to the point

"And what if I did?"

"Did you realize his feelings for you?"

"I did, I just acted like I didn't"

"Because of his fiancée, Princess Beatrix?" she nodded

"I could totally see how much she tries for Kai to notice her. This is why King Viktor wanted to talk to me about. For me not to have any contact with any of the Princes anymore, and as for Kai to be wedded to Princess Beatrix that maybe Kai will forget about me"

"But he didn't. You could say that his habits had changed once you stopped visiting" I then watched Prince Licht as I remembered the Princes getting sad every single day

"He shouldn't have, he has Princess Beatrix to do those everyday habits that we have done"

"It won't be the same though" she smiled meekly

"It is better for him to forget about me already"

"Sounds like you don't want him though" tears started streaming down her cheeks

"Even I can't" she then wiped her tears and stood up

"I'm sorry Professor. I need to get going" she quickly left the café. I took another sip of my drink and looked at the table that was closer to mine

"Did you listen carefully, Viktor?"

The next day, we saw Prince Kai with Princess Beatrix at the gardens. Which seemed that they are having a heavy discussion

"I wonder what they are talking about" Prince Leonhard said as he was staring at them

"I guess it's about their wedding that will happen the next following weeks" Prince Bruno commented, also watching them

"Cousin Beatrix is nice and all. But, I still want Older Brother Kai to end up with Older Sister (F/N)" Prince Licht grinned

"If only though"

The day has finally come for Prince Kai's wedding to Princess Beatrix and everyone is busy preparing. The grand ball has been designed for the reception and all of us headed to the church to where the wedding will commence.

I was inside the room of Prince Kai, with the other Princes who was trying ease his nerves. But we all knew that his not nervous about his wedding, his feeling are getting tormented. We then heard a knock on the door

"Your highness, it's time to go" Prince Kai nodded and left, followed by his brothers. We then rode a carriage, separate to Prince Kai, heading to the church.

I was seated with the Grannzreich family, as the wedding march started to play, all of us stood up to welcome the bride. As the door opened, we saw the bride, the veil covering her face. But as she was getting closer, the three youngest Princes started shoving each other which Viktor just grinned

"Isn't that Uncle?"

"Wait, does that mean?!"

"I'm getting confused here!"

As she got closer to the Prince Kai, his eyes turned wide as she said her name...

"(F/N)" I saw her head move as she nodded. She then looked at the Lothringen family, and there was Princess Beatrix smiling at the couple.

"You planned this, Viktor?" I asked to him as all of us sat down, the wedding to start

"More like, I helped. Princess Beatrix was the one who did it all. She heard us talking about Kai and also, I wasn't being a good father to not notice his feelings to her" I just smiled at the new happy couple, as their new life will start as husband and wife.