The serum would hold for approximately four hours.

Four hours of daylight. Four hours of pretending to be human.

Four hours to find out if the compound stabilized in natural sunlight or if I'd combust into ash in the middle of a crowded public space.

Science required field testing. That's what I told myself as I stood outside the laboratory at ten in the morning, squinting against the brightness that had been forbidden to me for two centuries.

The sun felt like a miracle. Like a violation. Like coming home to a house that had burned down while I was away.

"You okay?" Marcus stood beside me, close enough that I could feel the warmth radiating from his skin. He'd been gaining weight, filling out the hollows that cancer had carved into his frame. His scent was stronger now—cedar and rain and that underlying vitality that made my teeth ache.

"I'm not ash," I said. "So that's promising."

"Low bar."

"I'm a scientist. We celebrate incremental progress."

He smiled, and something in my chest twisted. He'd been smiling more lately. The gray tinge had faded from his skin, replaced by color I tried not to think about too hard. Color that came from my blood flowing through his veins, rewriting his cells, changing him in ways I was only beginning to understand.

Ways I'd spent the last week obsessively analyzing in my laboratory while pretending I wasn't avoiding him.

"Where are we going?" he asked.

"Botanical garden. Three blocks north." I'd chosen it carefully—public enough to be safe, isolated enough that if something went wrong, I wouldn't take civilians with me. "I need to test the serum's stability in various environmental conditions."

"You need to test if you can walk in a park without dying."

"That's what I said."

"You made it sound way more depressing."

I started walking before I could smile. Before I could acknowledge the warmth spreading through my chest that had nothing to do with sunlight.

The city looked different in daylight. Softer. More forgiving. The harsh edges I navigated by moonlight seemed gentler under the sun's glow, as if the world itself was kinder to those who could bear witness to it in full light.

People passed us on the sidewalk—humans going about their ordinary lives, unaware they were walking past a predator. A monster. A thing that shouldn't exist in their daylight world.

Marcus's hand brushed mine as we walked.

I jerked away like I'd been burned.

"Sorry," he said, not sounding sorry at all.

"Personal space."

"You literally drink my blood."

"That's medical."

"Right. Very professional."

I could hear his heartbeat. Steady and strong and so goddamn alive it made me want to weep. Or feed. Or both.

The botanical garden spread before us like something out of a dream I'd forgotten I'd had. Flowering trees lined the pathways, their blossoms almost painfully bright. The air smelled of jasmine and honeysuckle and fresh earth—scents I'd only experienced in darkness for so long I'd forgotten their full complexity.

"Jesus," Marcus breathed. "When's the last time you saw this?"

"Spring of 1824." The words came out before I could stop them. "There was a garden near the hospital where I worked. I used to eat my lunch there."

"What happened to it?"

"Turned into a parking lot sometime in the 1950s." I stepped onto the garden path, feeling sunlight warm my face. "Progress."

We walked in silence for a while. Marcus had brought his camera—an old film Leica that looked like it had survived a war. Probably because it had. He hadn't raised it yet, just carried it like a talisman against his chest.

"I thought you were a photojournalist," I said.

"Was."

"You don't take pictures anymore?"

His jaw tightened. "Haven't. Not since the diagnosis."

"Why not?"

"What's the point of capturing moments when you won't be around to remember them?"

I stopped walking. Turned to face him. "What's the point of remembering moments if you never captured them in the first place?"

He stared at me, something complicated moving behind his eyes. "That's surprisingly philosophical for someone who spends all her time in a lab."

"I've had two hundred years to think about it."

"And?"

"And I still don't have an answer." I looked up at the sun, feeling its warmth on my skin without the accompanying agony of burning. "But I'm starting to think the question matters more than the answer."

Marcus raised his camera.

The shutter clicked.

"What are you doing?" I demanded.

"Capturing a moment." Another click. "In case one of us wants to remember it later."

"I don't photograph well."

"Bullshit. You photograph like a goddamn renaissance painting." Click. "All those sharp angles and dramatic lighting. Very Caravaggio."

"Caravaggio painted religious scenes."

"Yeah, well." Click. "There's something pretty fucking miraculous about a vampire standing in sunlight, don't you think?"

I should have argued. Should have told him to stop. Should have maintained the professional distance that was eroding more every day.

Instead, I let him photograph me.

We walked deeper into the garden. Marcus shot sparingly—a flower, a play of light through leaves, my hand trailing along a stone wall. Each click of the shutter felt intimate, like he was collecting pieces of me I hadn't meant to share.

"Tell me something," he said eventually. "What do you miss most? About being human."

"That's a complicated question."

"We've got time. Your serum's good for another three hours."

I considered lying. Deflecting. Maintaining the clinical detachment that kept me safe.

But the sun was warm on my face, and Marcus was looking at me like I was something other than a monster, and I was so goddamn tired of lying.

"Strawberries," I said.

He blinked. "What?"

"I miss strawberries. The taste of them. The way the juice would run down your chin if they were perfectly ripe." I touched my throat, remembering. "I can consume human food now—the daywalker serum fixed that. But it all tastes like ash. Like I'm eating the memory of flavor instead of the thing itself."

"That's..." He shook his head. "That's fucking tragic."

"It's efficient. I don't need to eat, so it doesn't matter that I can't taste."

"Everything matters, Elara. That's the whole point."

"The point of what?"

"Being alive." He raised the camera again, capturing me mid-argument. "Even when you're dying. Even when you're already dead. The strawberries matter."

My throat tightened. "What do you miss? What did you stop letting yourself want when you got your diagnosis?"

The camera lowered. For a long moment, he just looked at me, and I could see him deciding whether to trust me with the truth.

"This," he said finally. "Exactly this."

"Walking in a garden?"

"Caring whether I see tomorrow." His voice went rough. "I spent six months making peace with dying, Elara. Letting go of everything I wanted because wanting hurt too much. And now..."

"Now?"

"Now I'm starting to want things again." He stepped closer. Close enough that I could feel his body heat, smell the cedar and rain scent of him mixed with something darker. "Dangerous things."

My hands were shaking. When had my hands started shaking?

"Marcus—"

"Take a picture with me."

I stared at him. "What?"

"A picture. Together." He flagged down a passing jogger, an older woman who smiled indulgently as Marcus handed her his camera and positioned us in front of a flowering cherry tree.

"I don't—" I started.

"Just stand there and look mysterious. You're good at that."

The woman raised the camera. Marcus's arm slid around my waist, pulling me against his side.

Heat. He was so warm it was almost painful, like standing too close to a fire after centuries in the cold. My body responded before my mind could catch up—leaning into him, seeking that warmth, craving it with an intensity that terrified me.

The shutter clicked.

"Beautiful couple," the woman said, handing back the camera.

Marcus didn't correct her.

Neither did I.

We walked on, but something had shifted. The air felt charged, heavy with things we weren't saying. Marcus's scent wrapped around me like a physical touch, and I caught myself swaying toward him, drawn by that vital warmth that sang to every predatory instinct I possessed.

Except it wasn't just hunger anymore.

That was the problem.

"Elara." Marcus had stopped walking. "Your neck."

I touched my throat and felt the blister forming. Felt the telltale prickle of skin beginning to burn.

"Fuck." I checked my watch. Three hours and forty-seven minutes. The serum was breaking down faster than my calculations predicted. "We need to get inside."

"How fast?"

Another blister erupted on my cheekbone. The sun that had felt like a blessing now burned like judgment.

"Fast."

Marcus grabbed my hand and ran.

We sprinted through the garden, my skin blistering with each passing second. Smoke began to rise from my exposed arms. The pain was excruciating—like being flayed alive, every nerve ending screaming.

The garden entrance was too far. We'd never make it.

"There." Marcus dragged me toward a maintenance shed, its door hanging open. We tumbled inside just as flames erupted across my shoulders.

The darkness was immediate relief, but the damage was done. I collapsed against the wall, my skin charred and blistered, smoke still rising from my burns.

"Jesus Christ." Marcus was on his knees beside me, his face pale. "What do you need? How do I help?"

"I'll heal." My voice came out strangled. "Give me a few minutes."

"A few minutes? You're literally smoking."

"I've survived worse."

"That's not the comfort you think it is."

I laughed, and it hurt. Everything hurt. But beneath the pain was something else—the memory of sunlight on my face, of Marcus's arm around my waist, of feeling almost human for three hours and forty-seven minutes.

Worth it.

The thought should have terrified me.

Instead, it felt like truth.

My skin was already beginning to knit itself back together, the burns fading from black to red to pink. Accelerated healing—one of the few benefits of being a monster.

Marcus watched the process with scientific fascination and something that looked like horror.

"Does it hurt?" he asked.

"Yes."

"Can I—" He reached out, then stopped. "Can I do anything?"

"You can stop looking at me like I'm going to shatter."

"You just caught fire, Elara. You're allowed to shatter a little."

"I don't shatter." But my hands were still shaking, and we both knew it.

He took my hand. His palm was warm against mine, his pulse steady and strong beneath my fingers. I should have pulled away. Should have maintained distance.

I held on tighter.

"Thank you," I said quietly. "For running with me. You could have left me."

"Why the fuck would I leave you?"

"Because I'm dangerous. Because being near me could get you killed. Because—"

"Because you're worth it," he interrupted. "Even when you're on fire. Especially then."

Something cracked open in my chest. Something I'd kept locked and frozen for two centuries.

"Marcus, I—"

The door burst open.

Sunlight flooded the shed, and I screamed as it hit my half-healed skin. Flames erupted again, worse this time, feeding on the fresh burns.

Marcus didn't hesitate.

He threw himself over me, shielding my body with his, taking the sunlight that would have reduced me to ash. I felt his body jerk as the UV radiation hit him, smelled his skin beginning to burn.

"Get off me!" I shoved at him, but he was immovable. "Marcus, you'll—"

"Shut up and let me do this."

He kicked the door closed with his foot, plunging us back into darkness. Then he collapsed beside me, gasping, his exposed arms blistered and raw.

"You idiot." My voice broke. "You beautiful, stupid idiot."

"Yeah, well." He tried to smile and failed. "We can't all be immortal."

The burns on his arms were severe—second-degree at least, the skin angry and weeping. He'd hurt himself for me. Damaged his mortal, fragile body to save a monster who would heal in minutes anyway.

I'd never hated myself more.

Or wanted someone more.

"I can help," I said. "My blood. It'll heal you."

He looked at me through pain-glazed eyes. "Your blood heals?"

"Among other things." I bit into my wrist, feeling my fangs slide free, tasting my own blood—cold and chemical and wrong. "Drink."

"Elara—"

"It's not turning you. It's just healing. But you have to drink it now before the wounds set."

He hesitated for only a second before pressing his mouth to my wrist.

The sensation nearly broke me.

His lips were warm against my skin, his tongue gentle as he lapped at the blood flowing from my self-inflicted wound. I felt the pull of him drinking, felt something in my chest respond to the intimacy of it.

This was different from feeding. Reversed. Inverted. I was sustaining him instead of taking from him, and the vulnerability of it was staggering.

His burns began to fade almost immediately, the skin knitting itself back together with unnatural speed. But he kept drinking, and I kept letting him, and we both knew this had stopped being about healing.

"Marcus." My voice came out breathless. "That's enough."

He pulled back slowly, his lips stained with my blood. His eyes were dark, pupils blown wide, and I could see my own hunger reflected back at me.

"Your blood tastes like starlight," he said roughly. "Like something I've been missing my whole life without knowing it."

"It's toxic. Addictive. You shouldn't—"

"I shouldn't want you?" He leaned closer, and I could feel his breath on my face. "Too late."

"This is a bad idea."

"I'm dying, Elara. All my ideas are bad." His hand came up to cup my face, thumb brushing my cheekbone. "At least this one feels good."

I should have pulled away. Should have maintained the boundaries that kept us both safe.

Instead, I closed my eyes and let myself feel his warmth, his touch, his impossible vitality.

"We should go," I whispered. "Before someone finds us."

"Yeah." But neither of us moved.

We sat in the darkness of the maintenance shed, my wrist still bleeding sluggishly between us, his hand still cradling my face. Outside, the sun continued its arc across the sky, indifferent to the monster and the dying man who'd found something worth burning for.

Something worth living for.

Something that would probably destroy us both.

"Elara?" Marcus's voice was soft in the darkness.

"Yeah?"

"I'm glad I didn't die before meeting you."

My throat closed. "I'm glad too."

It was the most honest thing I'd said in two hundred years.

And the most terrifying.

Because somewhere between the laboratory and the sunlight and this moment, I'd stopped seeing Marcus as a test subject. Stopped seeing him as a means to an end.

Started seeing him as someone I couldn't afford to lose.

Even though I would. Eventually. Inevitably.

Mortality was a promise that couldn't be broken, no matter how much my blood healed him.

Unless...

The thought crystallized in my mind with horrifying clarity. The way his cells responded to my blood. The way his cancer retreated. The way he'd healed from burns that should have scarred.

What if I could save him?

What if the research I'd spent two centuries pursuing could give Marcus what it had given me—time, endless time, immortality?

What if I could turn him?

The idea should have been repulsive. Should have been unthinkable.

Instead, it felt like hope.

And hope, I was learning, was the most dangerous thing of all.