Once the ingredients were located, May insisted they take several hours to rest (which Sirius was immensely grateful for, even if he failed to voice his gratitude- he still hadn't completely recovered yet). Luck was with them, too, as Balthazar's blood worked to activate the portal. "You go ahead," May told Sirius. "I'll stay here and keep watch, on the off chance someone discovers our presence here."

"Good thinking." He stared down at the swirling violet vortex that had opened in the floor, trying not to let his excitement overwhelm him. To think, he would actually get to see the Soul Cairn! He stepped down toward the portal, but was quickly forced to retreat, a strangled hiss of pain escaping him.

"Sirius!" May gasped, rushing forward to pull him back to safety. He let her, panting through the pain. "Are you alright?!"

"That looked like it hurt," Balthazar murmured in concern.

"It did," Sirius ground out, though now the pain was fading. "What was that?"

"I'm so sorry," Balthazar said, looking genuinely apologetic. "I should have thought of that. It's been so long since I was mortal, there are things I… forget to take into account." Sirius lifted an eyebrow at him, waiting. "It's hard to describe. The Soul Cairn is… hungry, for lack of a better word. It's trying to take your life essence as payment."

Sirius tried not to let his disappointment show. "So there's no way in, then."

"There might be, but I don't think you're going to like it," Balthazar admitted. "Vampires aren't counted among the living. I could likely go through without a problem."

The two elves were silent as that sank in. "There has to be another way," Sirius protested. Balthazar nodded in silent acceptance. He'd expected a refusal.

"Maybe. We could just 'pay the toll' another way. It wants a soul, so we give it a soul. Yours."

"Wouldn't that kill me?!"

"My mother taught me a trick or two. I could partially soul trap you, and offer that gem to the Ideal Masters. It might be enough to satisfy them. It would make you a bit weaker when we travel through the Soul Cairn, but we might be able to fix that once we're inside." He bit his lip. "Maybe."

"And those are his only two options?" May asked, looking worried.

"I'm sorry," Balthazar sighed. "I wish I knew a better way, something that would be easier to handle."

"Soul trap me," Sirius decided. "I wouldn't feel right as a vampire."

Balthazar nodded. "I promise to try and make this as painless as possible. Hold still." Sirius nodded stiffly, clenching his fists as the vampire cast the spell. There was a pinching sensation and he gasped at the sudden stab that went through him, but then it was over- and Balthazar was holding a piece of his soul.

"Oh," he breathed, staring as the vampire brought it to a soul gem to be absorbed. "That's…"

Balthazar quirked a smile at him. "Fascinating, isn't it? This should work, though." He approached the vortex and let the gem drop in.

"Are you okay?" May asked, gently touching Sirius' arm.

"I think so," he answered. "Honestly it felt more just weird than painful."

She nodded, accepting his answer. "Here," she said, and handed over a few potions.

"May, I can't-"

"Take them," she insisted. "If he's right about you being weaker while you're in there you're going to need them. I promised the Knight I'd look after you, and he'd be very cross with me if I returned you in worse shape than when we left."

Sirius gave her a strange look. "Why would he-"

"We should go now," Balthazar interrupted. "Before the offering wears off." Sirius sighed, accepting the potions and shoving them into his pack before following the vampire into the portal. He approached it with some trepidation, but this time there was no crushing, draining sensation. He passed through with no trouble. "Everything alright?" Balthazar asked, glancing up at him from a few steps down.

"It worked," Sirius answered with some amazement. "Impressive." Balthazar smiled back at him, quite pleased with their success. Sirius looked about. "Wow."

Balthazar nodded his agreement. "I'd heard stories about the Soul Cairn, but never thought I'd see it myself. So far it's… about what I imagined."

"Bleak and eerie?" Sirius snorted.

"Precisely." He started back down the stairs. "Let's go. My mother must be waiting on the other side of that thing." He gestured to a wall spanning the desolation as far as they could see. Beyond it, Sirius could just barely make out what looked like a fortress. He took in a deep breath, resting a hand on the hilt of his borrowed sword, and followed his vampire companion down into the mist below.