As his ox-cart jolted through the city wards, Hiromasa continued to think about his scent for the contest. Sandalwood was too obvious; musk too pungent; cloves too warm. Briefly he considered using flowers as a base before he realised that everyone else would do the same thing. Incense-blending was like music, he thought: he needed an underlying scent motif, one single perfect note, before he could try any variations.

And then it came to him, an idea beautiful in its simplicity. He would create something new, a blend that would intrigue and attract – a scent not based on the perfume of flowers or the heat of spice, but of human skin.

Hiromasa pressed his inner wrist to his nose. He could smell Winter Moon's perfume mixed in with his own sweat and the faint trace of ink. It was a comforting, not unpleasant scent, but hardly one that would win a prize. He needed something exotic and alluring, a perfume that would conjure different feelings in different people. He needed something simple and complex, something with an edge of bitterness and a touch of sweetness, a scent that could attract even those who found it peculiar.

In short, he needed Seimei's scent.

Hiromasa was sure his friend would help. He pulled aside the curtain and leaned out of the cart. "Take me to the house of Abe no Seimei!"

The gates opened to admit him. Hiromasa strode through the tangled wilderness of the garden, absently noting which flowers were still in season. Perhaps Seimei would consent to him using a few in the incense blend.

A female shikigami waited on the porch. Greeted by her silence and blank expression, Hiromasa realised that Seimei must still be at the palace. He hesitated, at first unwilling to enter the house while its master was absent, but then decided it was the ideal opportunity. He could make notes at his leisure, without fear of any arch commentary. Perhaps he could even smuggle away a ball of Seimei's incense for further examination.

Delicate footsteps sounded. Mitsumushi brushed past the shikigami, dismissing her with a glance. She turned to him and beamed over her armful of flowers. "Hiromasa!"

He bowed, which made the pretty butterfly-spirit giggle. Mitsumushi indicated that he should follow her, and led him to the veranda where he and Seimei usually sat. The shikigami waited in the shadows, holding a jug of sake and a cup. Mitsumushi gestured that he was to seat himself and wait for Seimei's return.

Hiromasa remained standing, feeling uncomfortable. Quite aside from the fact that he didn't know how long Seimei would stay at the palace, he'd come here for a reason and didn't want to get sidetracked by the sake.

He glanced at Mitsumushi, who was watching him with friendly interest. Hiromasa was never certain how much she understood. He didn't want to confuse her, but didn't know how best to explain himself. "I don't want to drink," he said. "I want perfume." He mimed sniffing his clothes. "Incense."

Mitsumushi nodded. She held out the flowers in her hands. "Perfume!"

"Not flower perfume," Hiromasa told her. "Seimei."

The butterfly-spirit looked confused. "Seimei? No."

Hiromasa sighed. "Do you mean Seimei doesn't use scent, or you don't know where he keeps it?"

"No scent." Mitsumushi smiled. "No scent!"

"But he must," Hiromasa protested. "He always smells so good…"

Mitsumushi tilted her head and beamed at him again, picking up on the last word. "Hiromasa is a very good man."

The familiar phrase brought him to his senses. A very good man wouldn't skulk in his friend's house in the hope of stealing incense. He was being ridiculous, and he felt glad Seimei wasn't there to pass comment on his actions.

Hiromasa sank to the floor with a sigh. Perhaps he would have one cup of sake before he went home. On a whim he sat in Seimei's usual place, leaning against the wooden pillar on the outside of the veranda while Mitsumushi poured the sake.

He accepted the cup, holding it balanced in one hand but not drinking from it. Hiromasa closed his eyes and breathed deeply. He could smell the sharpness of the alcohol and the brazen sweetness of Mitsumushi's discarded flowers. Beneath it, lingering in the warmth of the house, he caught Seimei's scent.

He opened his eyes and sat forward so quickly he spilled the sake. Immediately, Seimei's scent was lost. Hiromasa cursed. He put down the cup and licked the sake from his skin, conscious of its smell burning in his nose. He snorted, blinked, and caught the trace of scent again.

It teased him, now bold, now shy. Leaving the veranda, he followed it like a dog, scrambling from room to room to seek its source. He found nothing. Not even in the cold braziers did he discover a fleck of scented ash. Mitsumushi had been telling the truth: Seimei didn't use incense. The scent that perfumed his house, his clothes, his skin – it was either magic, or pure Seimei.

Hiromasa decided it didn't really matter what it was or where it came from. He had to master it, make it his own.

He took a piece of folded paper from his cloak. Borrowing an inkstone and brush from Seimei's study, Hiromasa made notes on the scent that lingered throughout the house. He tried to name its subtleties and the feelings each layer evoked. His thoughts emerged onto the paper as a strange kind of poetry: black ink damp earth/fox in wet bracken/shadows in sunlight/night-flowering spikenard hunger sex.

Hiromasa stared at the paper and tried to make sense of what he'd written. To him, sunlight smelled of lemon flowers, dried grass, dust and fire. None of those came close to the scent he knew from Seimei's skin. He didn't like spikenard, and how was he to recognise the scent of hunger?

Gloom descended. Perhaps he should just make a blend of lavender and late autumn roses, like everyone else. Hiromasa crumpled his notes and shoved the paper back inside his cloak.

Mitsumushi stood watching him, an expression of intense curiosity upon her face. A white glossed under-robe trailed from her arms. She offered it to him, saying, "Seimei. Scent."

Hiromasa took it. Cautiously at first, and then with intent, he sniffed the robe from collar to sleeve and down its length. Seimei had worn it closest to his skin while he'd slept. His scent was trapped in the cloth, every nuance of his body imprinted upon the beaten silk.

Elated, Hiromasa retrieved his poetic list and annotated his earlier remarks. This time, he would get it right. There would be no mistakes when he came to blend the incense. He furled the robe over his fist and held it beneath his nose. Breathing in only Seimei made his head swim. His other senses blurred as he focused on his task.

Hiromasa felt arousal thrum through him, a low-level desire provoked by the feel of silk in his hand and Seimei's scent wrapping around him. He wished Seimei was with him now, wished he could smell the scent from cool, naked skin rather than this garment tangled around his fingers.

"Ah!" Mitsumushi's cry jolted him out of his thoughts. He looked up to see the butterfly-spirit jump to her feet and move towards the front of the house. She giggled, turning to Hiromasa. "Seimei!"

"Seimei…"

Hiromasa dropped the robe as if it were on fire. The idea that his friend would find him like this, molesting his clothes and taking notes on the experience, filled him with shame. Embarrassed and guilty, he fled.

It still wasn't right.

In a fit of temper, Hiromasa swept his arm across the floor, spilling powder and colour. Crushed seashell glittered like frost. The honey pot fell over, a sticky golden trail oozing onto the floorboards. Petals drifted, sticking in the honey or skittering in a puff of breeze towards the garden.

Hiromasa sneezed. He rubbed his nose, certain he was coming down with a cold. He'd sniffed so many different scents he could no longer distinguish one from the other. Only the heavy richness of frankincense lingered, a smell that dominated the room and stood in complete opposition to the scent he wanted to create.

A headache hung behind his eyes. Hiromasa sighed and gave up on his experiments for a while. He went into the garden and took deep breaths, trying to dispel the myriad scents cluttering his memory. He found it difficult to take the air without attempting to identify every separate perfume borne along by the breeze. Frustrated, he went back indoors and lay down with a jug of sake.

The arrival of a messenger lifted Hiromasa from his gloom. The letter was written on pale pink Korean paper and knotted with a sprig of lavender so dry it snapped in his hands like tinder. Cautiously, he sniffed it, and recognised Winter Moon's scent.

He unfolded the letter, skipped the opening poem and scanned through several items of gossip before he found her answer to the question he'd asked this morning – how can one capture a person's scent?

About the incense contest, she wrote,

Well, I really shouldn't share confidential information, but you know, your mother was so helpful when I called on her and I don't think it's cheating to swap basic recipes, so I'll tell you. My own unique scent is praised by many people, you know, even the Empress remarked on it last year. So I'm not surprised you want to copy it. You must promise to burn this just as soon as you've made the incense, I don't want anyone else stealing my perfume. Anyway, here's the recipe…

Hiromasa stopped reading. She'd completely misunderstood him. He supposed it was his own fault for being so coy, but he could hardly tell her the truth.

Prompted by curiosity, he glanced at the letter again and examined Winter Moon's recipe. Lavender and late autumn roses, just as he'd thought, blended with Indian resin and sandalwood. Hiromasa wrinkled his nose. It seemed to him a dull fragrance lacking in any originality, but now she'd expect him to produce a variation.

"Damn," he muttered, returning to his ingredients. He looked at the poem-list he'd made at Seimei's house and began again, pouring a quantity of black ink over cloves and letting them steep.

More letters arrived throughout the afternoon. Hiromasa had written to every woman of his acquaintance and begged for help. Some ladies replied only to tease him gently for taking on such a difficult task. Others offered advice that, when he tried it, proved useless. Those women who'd known him more intimately in recent months made the same assumption as Winter Moon, and along with their secret recipes for their personal incense blends, they also enclosed fervent wishes to see him again as soon as the weather changed.

He piled these letters together and wondered what to do. Perhaps some fictional prince could cope with the demands of fifteen ladies at once, but Hiromasa doubted he had the stamina to try it. Besides, if he wanted to please all the ladies, he had to make all their perfumes. If he chose to make only one, it would be a humiliation for the rest. And if he failed completely, no woman, least of all the generous ladies who'd shared their secrets with him, would want to warm his bed during the winter months.

So he had to create a new perfume. There was no escaping it. He had to make Seimei's scent.

Hiromasa tried again, combining the advice and various methods outlined in the letters. He tried pounding the incense in the garden, and then on the porch. He dispatched a servant to fetch water from a mountain spring. He experimented with mixing scents with the ashes from different types of wood. Still Seimei's scent evaded him.

As the sun lowered, one final letter arrived. The sender was a lady Hiromasa had nicknamed Cloudy Days, a woman who balanced glittering wit with bitter resignation. He was rather frightened of her, but she'd always been kind to him, even after their brief affair ended. He read her message while he ate his evening rice:

I hear you've been writing to every woman at court about this incense-blending contest. Silly boy, don't you know that all the fragrances you smell on your lovers are created by the same person? Ignore any advice they may give and don't try any of their so-called 'secret recipes'. If you want a perfume, any kind of perfume, go outside the city to the west and look for the house of a woman they call Nose. Offer her more than anyone else has promised, and you'll win the contest.

Hiromasa read it twice then jumped to his feet. He left his meal half finished and strode out of the house still adjusting the hat upon his head, his formal cloak trailing as he hurried towards the western gate.