General dissatisfaction

As Soisen feared, his stay in the infirmary was extremely dull, with the exception of the first few days' visits from his friends plus Silvia's daily visit, which Pomfrey very kindly extended to ten minutes after much deliberation, persuasion and Silvia's secret use of a potion Soisen developed in the past for fun called Puppy Eyes. Extremely effective to date.

Young love, how envious....

-You were right about Umbridge," Silvia told him as she gave him some tender pear that she cut herself, "Everything we have done so far in DADA has been purely theoretical and anything not in the book is considered "inappropriate in the Ministry's opinion", so no one has used a single spell in her class. If we only have to read the book during his lessons, what's the point of him being at Hogwarts?

-It's the Minister's paranoia, Dumbledore has no choice but to put up with it for now," he said, "Did he give you any trouble when you handed in my homework? -Soisen asked, a bit worried about his girlfriend.

Yes, apparently, Umbridge's being sick was no excuse to avoid doing DADA homework. As long as he could move his hands to write, he had to do his homework like the rest of the students. But since he had to stay in the infirmary, he had to ask Silvia to deliver the scrolls instead.

Honestly, Soisen was pretty sure it was her revenge for gracefully interrupting his speech on the first day of school.

-Apart from an annoyed look for not finding fault with your work? No, all good," laughed Silvia as she remembered the expression the pink witch had when she couldn't find a reason to take points off, "Although I suspect she doesn't like you.

-Good. It would be annoying if she thought she could use me as a henchman," Soisen snorted. He had made no secret of his displeasure at any time and other than a polite demeanor to not give this woman excuses to cause him trouble, he shouldn't expect anything more from him- Any interesting developments at school?

-Potter is not happy with Umbridge's curriculum and Hermione has been keeping an eye on him to prevent him from doing anything that would cause problems for Gryffindor," commented Silvia after remembering for a moment, "According to her observations, she suspects that he, Ron and others want to set up some sort of secret study group, where Potter would teach in a practical way how to use defense spells. But they haven't invited her, and it seems that when they realize she's around, they change the subject.

-And how did she find out about the plan then? They should... Wait, Ron?

-Ron.

-That explains it all, it makes sense.

-I suspect he wants to take advantage of the fact that he has a decent level of spell casting compared to the rest (not including us), to subvert the negative opinion he's been getting these days since school started. Apparently, many students almost didn't return because of how he proclaimed that the dark lord had risen and they hold a grudge to some degree -Silvia added- It seems they will have a meeting at the Hog's Head to see how many people they can gather. Also, I have some bad news.

-How bad?

-Well, apparently Professor McGonagall found out about their plans and "coincidentally" leaked the existence of that place, the one in front of a certain tapestry -Silvia didn't know if anyone was eavesdropping on them, but the information was complete in her unspoken understanding- So I think it's very likely that they will decide to use that place for their group.

-That would be... very annoying -Soisen couldn't help but frown.

While he knew how Dumbledore's Army would occupy the Hall of Menesters to conduct their activities in the original timeline, he hoped that with Hermione's absence and clever assistance, they would try to use the Shrieking House instead.

That room had been practically a private place for him, Sylvia and Hermione where they could practice magic unrestricted and very conveniently, making more people aware of the place would only hinder its use.

And McGonagall's intervention reeked of a crazy old Lemon Drops and Licorice Roaches lover.

-Don't worry, they'll have to find another place," Soisen said to reassure Silvia.

The magical fusion was in its final step and tomorrow the castle will recognize him as its master. He only needs a thought to prevent such a room from manifesting even if the conditions are met, effectively denying him access to it. He would have absolute control of every hanging painting, floating ladder, animated armor, torch and blade of weeds as long as he is within the castle's influence. He could even have the entrance change floors and open wherever he wished or change the conditions for entry.

Truly absolute control.

Not even Dumbledore or any headmaster would have more authority than him in this place.

His only doubt is whether the thousand year old basilisk will also be subdued, as he doesn't know if the castle's authority is greater than that of the heir of Slytherin or even related in any way.

As for students joining Potter for practice, what do they have to do with him?

Anyone with two brain cells in their brain would look for someone really capable if they want to learn and really improve, Potter wasn't really the best choice in either case. Ravenclaw had Cho, Hufflepuff had Silvia and Cedric, Gryffindor had Hermione and Galegold had him, Ginny and Luna.

Slytherin had... Snape?

Anyway, he himself intended to be a DADA "teacher" this year for members of his House and members of the Order of the Hippogriff. After all, he already knew perfectly well all the studies up to seventh year and the only reason he didn't graduate early was because there was no such option when his acquaintances and girlfriend would have to spend two more years in this place without him.

Leave them under Dumbledore's influence and manipulation? No, definitely not.

The conversation with Ginny on the express revealed that the Black house was still operational as a central base for members of the Order of the Phoenix, though he didn't know the exact way Dumbledore managed it.

So, his plan for the year was as follows:

1- Claim ownership of Hogwarts Castle and begin modifying it in secret.

2- Deal with Umbridge if she dares to step out of line.

3- Help the Weasley twins open their store when they run away.

4- Finish the magical bastion.

5- Use his knowledge and gifts to train his people and prepare them for what is to come.

6- ...

-Okay -Silvia nodded and offered him another piece of fruit to eat- I saw the diagram you sent me, I think we could start the modifications with....

While Soisen hadn't explained to anyone how he would inherit and control the castle, Silvia was an observant and intelligent girl and knew that her boyfriend had some rather unique special methods. If he said they wouldn't be able to use the room, he had some way to back up his words with confidence. Everyone had their secrets and she would wait patiently for her other half to tell her everything when the time came.

...Several minutes later....

-Time's up! -Pomfrey ejected Silvia from the infirmary at the end of the tenth exact minute, "The patient needs to rest.

Silvia smiled and nodded as she left and walked towards the Hufflepuff common room while unconsciously licking her lips, which had a sweet pear aftertaste.