Thanks to all of you who took the time to review my story!
Chapter betaed by Miette :)
AN: the reviews from the past month were full of remarks and hypothesis for the future, it put my brain in creativity mode and now, the story will be one chapter longer than planned thanks to you :)
AN-2021/03/05:Many thanks to dstone12 for correcting the mistakes left by Miette and I :)

Snape—Caspian now—was a thorn in her side.
She had believed she had overestimated him when he had come back with four Masteries only to spend two months doing nothing to increase his influence over the group. Even better, he had shown himself to be too soft-hearted to go after Muggles—she did not buy his excuses of disliking to waste his time with easy targets. She had almost forgotten he had been Abraxas Malfoy's mentoree.
After her set-up to definitely erase him from her Lord's memory had failed—she had thought Beltram had been over-kill and how wrong she had been—, she should have known that Caspian had had other plans to replace her as her Lord's favourite. The last poll had shown a sudden increase of vote intentions in favour of her Lord, and the younger members had labelled it the Caspian effect, the name spreading over the group, and even she had to admit it was aptly named. The creation of his own House, solely on his power and alliances, as well as his Lupacem had been a tremendous help when their campaign had been in need of a second breath. Caspian had completely changed the game.
Yet, she knew her Lord. He admired Caspian. He saw himself in him. As such, he was wary of him. One of the few remaining Death Eaters who did not bear his Mark. Her Lord wondered if the younger man might be building up to becoming the group's candidate for the coming election. She would watch him carefully. And she would crush him the moment he showed weakness. It was only a matter of time.

He would not let his efforts of the last four years be for naught.
He had worked so hard in sixth year to become Slytherin's king, his only credible competition gone from Hogwarts or too busy to play the game. He had cultivated the younger years carefully, until his parents' ideas had spread to the majority of Slytherin. After Hogwarts, he had done everything to make himself indispensable to the group, until he had had Lord Voldemort's ear. Last year, he had become the Death Eater's official secretary. Everyone knew that the best way to put a proposal on the agenda was to speak with him.
But today, those under twenty-five were fawning over Snape. Caspian. As if a new name would make him less Halfblood than he was. And Snape was far more suited to the genius' prickly personality. He had not been able to put a stop to Hogwarts' genius rumours, but as long as Snape had been far away working on his Apprenticeship, he had been able to adroitly suggest that rumours always were exaggerated. Then, Snape had come back with four Masteries, two grade I, and the rumours had increased. Everyone had waited with baited breath for Snape's next move, expecting him to court followers to build his own faction inside the group. Most of their members were either on his and Lord Lestrange's side, or on Lord Prince and Lord Greengrass' side, though the latter's numbers had dwindled lately with the death of several of the older members. The group had expected Snape to either seize the remaining neutral Death Eaters, or to challenge him for the leadership of the youngest members. To everyone's surprise and disappointment, he had done neither, seemingly content to renew his friendships with Malfoy, Wilkes, Rosier and Black. It was so un-Slytherin, and combined with his refusal to partake in the raids, he had had an easy time spreading other rumours. That their supposed genius was weak. Useless to the cause.
They were finally beginning to believe him, when Bellatrix had botched their attempt at discrediting Snape for good. Even then, Snape's victory had not been enough to earn him back his previous genius' status. But before he could finish crushing Snape's reputation and credibility, this Halfblood had had the gall to create his own House and the potion for Werewolves that all famous researchers had tried and failed to create for the past centuries. Lord Caspian. The last meeting had been full of adoration for the new Lord. Only Bellatrix seemed untouched by Snape's newfound grace.
At least, he knew he was enraging Snape by spending a lot of time with Rosier. Snape might have a good poker face, but he was watching him. Snape despised the fact that his old trio of friends was not as tight as they had once been. Which reminded him that he needed to find a new project to assign to Rosier. Since Snape's return, Rosier had been spending less time with him and his group, and it showed. Rosier's easy laughter and charm was one of the reasons he had gathered so much sympathy and followers. If Snape grabbed Rosier back, the new Lord would greatly improve his chances at climbing up in the group.
He may have underestimated Snape's slytherin's sense after all. The Halfblood had chosen Wilkes and Rosier in their first year.

He was so happy to finally have their trio back. The past years had not been the same without both Severus and Jonathan by his side.
Of course, things had changed since their fifth year. He had always believed in Severus' intelligence, but his friend's last successes made himself feel almost insignificant. He was the least gifted of the three of them. Jonathan had taken on the role of Head of his House after his father's death with remarkable facility. Severus had done even better by creating his own House among other prowesses. He was nowhere near their league.
He had thought himself had been doing well in his Apprenticeship when his Master had suddenly taken real notice of him after his first year and began investing more time in him. But lately, his Master was always telling him that he should do more, study more, practice more. His Master did not understand that the cause was more important. His Master did not care for politics.
Mulciber understood, contrary to Severus and Jonathan. It was so hard to live up to his friends' expectations. It was so easy for them, they did not understand that it was different for him.
Sometimes, he wondered if they were as invested in the cause as he was. Which was stupid. Severus had created the potion to help Werewolves, and Jonathan always tried to look out for the groups' best interests. But he was not certain that their idea of the group's future was the same as Mulciber's.
Himself did not know which one he would choose if asked to.

What a wonderful surprise. He had been so ashamed after his lost duel against Snape. At the time, he had not believed the youngest members' rumours calling him a genius, even seeing in him the future Merlin. Four Masteries were an impressive feat on paper, but everyone knew that foreign Masters often were more lenient than British ones. He knew better now.
At first, when he had heard that Snape had created his own House, he had thought that he had used a sponsor House like Prince or Malfoy, which would have been an impressive feat. But no record of vassality to either House had been recorded at Gringotts. Caspian had created his House on his own power. When you added his Lupacem's success, the young man was a serious asset for their group. He would love to discuss Magic Defence with him. During their duel, he had realised there was a side of Magic he did not know how to use. It opened new opportunities for him, which he had not believed possible at forty. He did not have Head of House duties so he was free to spend time researching when he was not working for the group.
He wondered why Caspian had not been recruited to help with training sessions. He had no doubt he could teach all of them a few useful tricks.

She was so glad to see Abraxas' Mentoree finally living up to his potential. They were definitely short of strong figures to support Slytherin's true side.
She did not regret getting involved in plan Slytherin ten years ago. They had needed to put a stop to the Ministry's madness which was destroying the core of their world under the pretext of helping Muggleborns assimilate. However, she might have miscalculated. She had thought Tom to be the perfect candidate to represent their cause. Both Augustus and Abraxas had agreed with her. And at the beginning, he had been everything she had believed him to be. Charismatic with a drop of arrogance, a remarkable mind and deep knowledge of Magic. And first and foremost, a true believer in Slytherin's rules. He had united all their fragmented factions, organised them into a coherent group. He had reigned in their most distasteful yet still useful members. She had thought they would win against Birkins. She had thought they would finally show Dumbledore what he could do with his lemon drops.
But the wind had changed. It had begun with Abraxas' death, and gone downhill from there. Tom had stopped requesting private meetings with Augustus and her. Instead, he listened to Rodolphus, Bellatrix, Orion and Mulciber Jr.
She was scared. For their cause, but also for her life and her family's. She had lost several friends the last few years, and while all deaths had been deemed natural, she had serious doubts.
Yes, the new Lord Caspian was a breath of fresh air. She would still check on her contingency plans.

PS: if you had doubts, by order of apparition, Bellatrix, Mulciber, Evan, Beltram and Lady Greengrass.