Once the coughing subsides, Orpheus tells Eurydice, "I do wish you could perform at court with me, yourself. This method... I do not know how it shall compare."
"Orphy, we've been over this," she says. They have. Of course, they have. He hasn't forgotten.
It's just that the more he becomes aware of the part of her that will accompany him—seeded in his heart like an overripe fruit, roots curving around his lungs and throat and all the way to his fingers on the lyre strings—the more he misses the part of her he'll be leaving behind.
"I just don't think I can leave here anymore." She lifts her skirts enough to bare her ankles, the gnarled knots of living wood that bind her to the floors of the chamber. Orpheus has seen them before. They twist and grow to allow her to walk back and forth anywhere in this little nook, but no further. "This is my home now."
"Our home," he corrects. He used to expect to be challenged on that possessive at first, the first few dozen visits after their reunion, but now Eurydice smiles whenever he says it. That's why he does.
"We're each other's home, and when you leave you'll take me with you." Inside his dead chest, flowers blossom: poppies and marigolds and plums like those that adorn her hair this season, weaving through her braids. Branches burrow in the deepest crevices of himself and endure despite the unending darkness around. That is what love means. "I'm with you, even when you can't see me. You know that by now, don't you?"
He does know.
What the mind knows, the heart sometimes hesitates to accept. This is no exception. After he returns to Lord Hades' court, Orpheus is conscious of Eurydice's roots seeded inside him with every breath, but it isn't until he starts playing their repertoire that he truly feels her presence.
Like the wind finds its voice in the gaps through dangling leaves, so does Eurydice's alto arise from the air through his thornbush lungs. It's a weak harmony at first, while her roots are still tender. Though some occupants of the House pause bemusedly to listen, as if questioning if they imagined it, none ask him about it.
The Queen is the first to do so, when she returns from her stay upon Olympus. On the surface, autumn must be turning the landscape a rich mixture of reds and browns; here at court Orpheus has started coughing up dying petals. In-between songs he gathers them into a pile by the wall behind him, in hopes that the earnest maid Dusa won't find them and clear them away.
Queen Persephone tells him, "Those are beautiful flowers. They shall never be uprooted from these halls, of that you have my word."
And within a candle's time a sapling sprouts from the pile of dead petals and begins to grow upward along the wall, to the invisible ceiling that appears as shadow to the naked eye. Perhaps, once fully grown, it may reach beyond the House, all the way up to Asphodel above. Roots reaching for roots, entwining. Eurydice's voice rings clearer within his as time goes on.
"Feels like I'm listening to both of you sing," Prince Zagreus comments, one day-or-night. He likes to submit requests, but Orpheus has to offer first, or he won't wish to disturb. "I could go sit too close to the fireplace for comfort, close my eyes, and picture myself up there in your home. Minus the mouth-watering smell of Eurydice's cooking, of course, but—close enough."
"I'm glad you appreciate our duets, my friend," Orpheus replies. "Tell me, how is our tree faring of late? I hope the coming winter isn't affecting it too severely."
He could see for himself if he just looked back, but some habits are worth breaking. He wrote a whole song about this one. Zagreus sits on the floor, presumably in order to see the top of the canopy, and he describes the structure beautifully: the twisting trunk, the clusters of flowers that emerge from the bark and let their petals flutter to the marble floors, poppies and marigolds and plums. The prince's observations could well be immortalized in song. Orpheus makes note of his words as he plucks a few scales with wood-knotted fingers, slowly, still learning dexterity with that extension of himself. A few more ballads and he'll be able to return home, and hold Eurydice beside him as well as within.
Until then, he sings.