"So, you followed the orders exactly as commanded, didn't you?" Hermione asked gently, "Not disobeying a single one?"
Kreacher nodded.
"What happened after you returned?" Dumbledore asked. "When you told your master what happened, what did Regulus say?"
"Young Master Regulus was very worried, extremely worried," Kreacher croaked, "Regulus told Kreacher to hide, not to leave the house." Then... after a while... one night, Young Master Regulus came to the cupboard to find Kreacher. Young Master Regulus seemed odd, not like his usual self, Kreacher could tell he was troubled inside... Master asked Kreacher to take him to the cave, the same cave Kreacher had gone to with the Dark Demon King..."
Little Sirius was stunned.
He furrowed his brows and asked coldly, "So, he made you drink the potion?"
Kreacher shook his head, bursting into tears.
Little Sirius suddenly stood up, a suspicion forming in his heart—he had already guessed the outcome of Regulus...
"Re—Young Master Regulus took a pendant box out of his pocket, just like the Dark Demon King's," Kreacher said, tears streaming down the sides of his long nose, "He told Kreacher to hold it, and after the stone basin was dry, to swap the pendant boxes..."
Kreacher's sobbing became coarse and harsh, and Harry had to concentrate fully to understand him.
"He ordered—Kreacher to leave—never mind him. He told Kreacher—to go home—not to tell Mistress—what he did—but had to destroy—the first pendant box. Then he drank—it dry—Kreacher swapped the pendant box—watched with open eyes... Young Master Regulus... dragged underwater... then..."
Little Sirius, hearing Kreacher's words, understood completely what had happened.
He stepped back two paces, seeming to realize what his brother had gone through...
Lupin quickly supported him, preventing Little Sirius from falling to the ground.
"Oh, Kreacher!" Hermione wailed, crying while kneeling beside the little elf, wanting to comfort him with a hug.
The little elf immediately stood up, backing away with evident disgust.
"Mudblood touched Kreacher! Stay away from Kreacher!"
Hermione stood frozen with her hands open, a bit at a loss, unsure of what to do next.
Repeatedly trying to be kind to the little elf, only to be mercilessly rejected and insulted, even Hermione, with her saintly patience, couldn't handle it anymore.
"I said! Don't call her that!"
Little Sirius came to his senses and shouted angrily.
"Kreacher apologizes to Young Master Regulus! Apologizes to Mistress!"
Kreacher wailed, lying on the bed, panting heavily, trembling all over, with shiny green mucus around his nose that seemed to be his snot.
Little Sirius sighed, impatiently pacing back and forth, clutching his head in distress and said sorrowfully, "This child... he should have come to me... should have sought my help, why was he so foolish to choose to bear it all alone? Merlin..."
"Because Young Master Sirius, you didn't believe in him." Kreacher managed to mock Little Sirius: "Young Master Regulus told Kreacher, he said Young Master Sirius thought he was a die-hard Death Eater and didn't believe in him..."
Hearing Kreacher say this, Little Sirius became even more despondent.
"Yes, yes, you're right..." Little Sirius pounded the bed with frustration, "If only I could have cared for him a little more—I'm damnable, utterly damnable, why couldn't I care for my own brother?"
Upon learning that his brother was not simply a loyal follower of the Death Eaters, Little Sirius felt immeasurable regret.
Yet at the same time, he also felt a bit proud.
"This isn't your fault." Lupin timely comforted, stepping forward, "Bigfoot, no one could know Regulus would oppose Voldemort... after all, we've never seen anyone betray the Dark Demon King."
Snape cleared his throat, attempting to remind Lupin that people betraying the Dark Demon King numbered more than one, and he was standing right in front of him.
"Now, I'm not the only one in this house against the Dark Demon King!" Little Sirius sniffed, proudly saying: "Look, there's Regulus too—my brother, he couldn't stand the ways of the Dark Demon King either. I knew it, I knew my brother wasn't the sort of person to be deceived by Voldemort!"
He held his head high, allowing the tears to flow freely, but his face was full of pride.
"So, you brought the Slytherin locket back home," Vivi lowered her head, determined to know the entire story, "Did you try to destroy it?"
"Kreacher couldn't leave a mark on it," the little elf said sadly, "Kreacher tried every way, every way, but none, not one succeeded... there was such powerful magic on the box, Kreacher believed it could only be destroyed from the inside, but it couldn't be opened... Kreacher punished himself, tried again, and punished himself, trying again. Kreacher couldn't fulfill the order, couldn't destroy the pendant box! Mistress was driven mad with grief because Young Master Regulus was missing, Kreacher couldn't tell her what happened, couldn't, because Young Master Regulus forbade—he forbade him to tell the family—what happened in the cave..."
"Forgive me for disobeying your orders, Young Master Regulus..." Kreacher banged his head against the wall, only to be restrained by Vivi's magic spell.
"But, Kreacher really wanted you to come back safe!" Kreacher sobbed and said, "Later, Mistress died, and then, just last year... the pendant box suddenly erupted with a black mist, and from that point, Kreacher knew nothing until you came and saved Kreacher."