As I begin to lead Aethon from the barn, drenched in its char-black wood and glowing firelight, my heart pounds with the truth of my mischief. Clearly, Alastor senses something is off with me, because he lets out a loud noise of distress before kicking the back of his stall madly.

Immediately, the other two join him.

Aethon digs in his heels, black eyes settling on me warily.

I hear noise in the room with the stable boy and my heart lurches.

I tell Aethon, “I’ll go alone, but I’ll be safer with you.”

If indecision could war in a horse’s eyes, Aethon would be the poster horse. The stable boy’s door snaps open and my body lurches to flee when Aethon bends as though to offer me onto his back. I climb quickly on top, and he shoots from the barn as the stable boy yells something to our retreating backs.

“To the Grove of Persephone,” I call, trying to ease the frantic notes that cling to my words. Aether’s hooves pound the earth as he moves quickly over the ground. Far quicker than any horse in the earthly realm could ever hope to move.

With the Palace of Hades in the distance, Asphodel City begins to glow brighter. The desire to slow Aethon—to explore the city and the souls living and thriving in the Underworld is strong. But it’s not strong enough to battle out the call that propels me forward in this journey I am no longer able to deny.

The Pool of Lethe and House of Thanatos fly by. Over the River Lethe that glitters with the blue of its agate bed, I can see the tall stone of the House of Hypnos. Where the House of Thanatos is black, like the Palace of Hades, the House of Hypnos is white marble with swirling black veins that drift into faded shadows. Like dreams lost to the ether.

When we cross the border of the Grove of Persephone, I urge Aethon on. Deeper in the forest, between the thick of the Weeping Pines, Aethon moves. He moves until we’ve hit the wall of the white mountain.

Prickles of awareness spread over every inch of my body as the urging sensation, a voiceless instinct pushing me forward, heightens.

Like I knew what I was to do when I first woke, I know what I am to do now.

Sliding from Aethon’s back, I give him a rub that he pushes into. I whisper, “Go back to the Palace of Hades.”

He whinnies like he doesn’t like my plan.

I press a kiss to his thick neck and turn to the white mountain. I’ve climbed only a few steps when I feel a tug on my cape. Glancing over my shoulder, I see the determined set of Aethon’s eyes as he clamps the fabric between his teeth. I try to pull, but he only tugs back in response.

Betrayal stings in my heart, because I know that must be what he is feeling now. My betrayal. And knowing that I’m hurting him hurts me.

“I’m sorry.” I inhale a gasp. “I—I have to.”

Aethon huffs through his nose but doesn’t release my cape.

Gathering my gown in one hand, I unclasp the cape from around my neck and hurry out of his reach up the White Mountain.

When I look over my shoulder again, the betrayal I sensed burns bright in his black eyes.

My voice shakes with emotion. Indecision wars inside me. I shake my head desperately. “Please understand,” I beg.I’m begging a horse to understand something I don’t even understand. “I have to do this.” My hand palms my low belly where I feel the brunt of the pull. The instinct I can’t ignore. “Please.”

When a tear falls from my eye, Aethon’s dark eyes darken. There’s so much understanding from this horse, from my friend, that it physically hurts me.

With a huff, he drops the cape and charges back through the forest toward the Palace of Hades. I know he’s going to alert Hades and turn quickly back to the White Mountain. Now, it’s a race against time.

In his Gods’ Form, I have no doubt Hades could get to Tartarus in very little time.

I have to get there first.

But it’s seriously not easy to climb a mountain in a gown. I have half a thought to just strip naked, but the idea has my flesh burning too hot to commit to.

By the time I crest the top, I’m sweating and breathing hard. Inside my chest, my heart is raging a war it has no hope of winning.

With a glance back at the Grove of Persephone, I begin the descent. This time, I don’t descend into the land that borders Tartarus, where the River Phlegethon boils as it rolls over screaming souls. Just thinking of the Elm of False Dreams gives me a shiver I grit my teeth to fight. The descent from the White Mountain into Tartarus is clearly not supposed to be done, as the stone is far steeper, and slippery with the heat that radiates up from the boiling River Phlegethon.

Unlike on the descent into the Elm of False Dreams, there are no steps carved into the mountain. My heart leaps as I slip on the steam-misted stone, catching myself just in time. I don’t know what will befall me if I slip into the River Phlegethon and its soul-boiling doom.

Clutching at the stone that holds me, I dare a peek over my shoulder before looking back up at the way I’d come. I’m going to have to find another way out of Tartarus, because there’s no way I can climb back the way I came. It’s too steep. Too misted with steam. Treacherous.