What Eren had given Marie was a concoction derived from his blood.
Alephee had prevented Eren from using his blood directly in any potioning experiment. Especially if those experiments were going to be conducted by someone else.
She had taught him a potioning method to extract the properties of his blood that gave it its no-elemental conflict nature. The process got rid of any other attributes that made it his blood. Therefore, the concoction resembled water.
This colorless liquid would show various properties from time to time. In some cases, it would not reflect any light that fell on it, turning the liquid completely black. Sometimes it would defy gravity and not fall into the vessel even if the vial was tilted so that it was poured outside.
Sometimes this liquid would stop being colorless and exude brilliance in distinct shades. And sometimes it would change its phase– turning gaseous from liquid and solid from gaseous before finally reverting to being liquid within a fraction of a second.
Alephee told Eren that this was the normal reaction for the extracted liquid. Only after confirming that the liquid did not have any blood-like properties did she give him her green signal to hand it over to Marie.
***
Eren was surprised when Marie hugged him with her emotions all over the place. But that didn't stop him from patting her back as he spoke up.
"You should control your emotions now. You are acting like your search is over when it has just begun. We are just getting started."
Eren tried to calm Marie with his words. But the latter had many things swirling inside her head. She couldn't help remembering the struggles she had to face.
She felt grateful that Eren proved her hypothesis right. But there was one part of her that wanted to discredit the derived solution. Because that part of her thought that only she had the right to discover it through the process she had created for herself. She wanted to be the one to claim the discovery of the missing ingredient.
Eren chuckled and caressed Marie's back before commenting.
"Hehe. Trust me. You wouldn't have been able to come up with the missing ingredient no matter how much you thought you were near to discovering it.
This concoction in your hand is something only I can give you. No matter how many years you spend researching your hypothesis, you wouldn't be able to produce even a single drop."
Marie was shocked when she heard Eren's words. Her ego as a researcher was telling her he was wrong. But there was something deep inside her that told her that Eren was speaking the truth.
The missing ingredient she had been looking for was always elusive. She always thought she was close to distilling it but the experiments would often go haywire at the last moment. But then how did Eren manage to derive the solution after reading her research papers and her hypothesis?
It meant that only Eren had the missing piece of the puzzle that validated her hypothesis and her research. Therefore, only he could make this concoction a reality.
In the end, Marie accepted the fact that Eren was telling the truth. That nobody but him could produce the missing ingredient. He had little to gain from lying about it.
Still, she wanted to learn more about this elusive ingredient.
"How…?"
Marie asked Eren in simple words. Eren pursed his lips before responding casually.
"um... It's a long process. Something you shouldn't worry too much about. After all, we all have our secrets. Potioners have them even more so than the rest."
Before Marie could ask Eren any more questions, she felt a strong tug on her shoulders. Arizihana had appeared behind Marie, trying to separate her from hugging Eren.
Eren raised his eyebrows before focusing his attention on Arizihana.
"Jealous much?"
Eren asked, a mischievous smile on his face. He could read what was transpiring inside Arizihana's head. He was a bit taken aback after realizing the fact that both the ladies were in fact "scissors sisters."
"What… what has that got to do with you, Adept Eren?"
Arizihana said with signs of stress on her face. Eren laughed before using his hand to pull the elf into his embrace as well.
Arizihana was shocked when she found herself resting her head on Eren's chest beside Marie. She could not believe that a senior ranker and their guild master would initiate such advances on her.
"Adept Eren… what is the meaning of this?"
Arizihana asked, giving up on her attempt to rescue Marie from Eren's embrace. The halfling was an emotional glob at the time.
"The meaning is simple. I want to brand you both."
Using his Sin Series Ability in conjunction with his soul sense, Eren said. This was one of the enlightenment he had received while awakening the soul sense.
Eren used his soul sense as a foundation to mimic the triggers of his Ability. In the next moment, both Marie and Arizihana felt that something had touched their inner vaginal walls.
Mark of the Seven Sins: Mist of Lust
Eren was able to activate his Ability without the penial penetration that was supposed to be its trigger. Since it was his soul sense that had been manifested in the way it did, the Ability's runes treated it as him fulfilling the trigger. After all, a person's soul sense was the most fundamental manifestation of himself.
Of course, only the mist of lust was activated this way. The branding process still required the usual action.
Both Marie and Arizihana kept looking at each other to figure out what was going on. But before they could process what was happening, the ladies started feeling waves of lust and ecstasy taking over them.
Eren didn't shy away from using the Ability on both the ladies even after knowing their "preferences". After all, he needed complete control over the experiments Marie was supposed to spearhead. And there was no better way to do it than branding them with his Sin Series Ability.
No matter how emotionally responsive he got, the butcher's self-interests were still paramount to him.
Both Marie and Arizihana were lower in ranking status than Eren. They couldn't offer any resistance to Eren's Ability that had been refined with his rank-up.
"Hehe. Let's get you ladies straightened up."
Eren chuckled at his pun as he hugged a halfling and an elf who had started writhing in lust in his embrace.
AN: The first instance of soul sense and Sin Series Abilities fusion took place in chapter 541.
