Hearthglass

You don't let her go to her seminar. You don't let her go anywhere. You get her back up the stairs with her arm around your neck and her boots dragging, and she lets you, which tells you more about how bad it is than anything she could say.

At her door she stops.

"This is as far as you come," she says. Not unkindly.

"I know."

"I'm not being dramatic. It's a rule. I need rules right now." She slides out from under your arm and leans on the frame. "Thank you. Go eat something. You skipped lunch, I could tell."

"How could you possibly tell that?"

"You were hungry and thinking about me at the same time," she says, and shuts the door.

The new postdoc arrives on Thursday.

Dr. Brack brings her down to the basement personally, which she has never done for anyone, and says, "Clodagh Dunleigh, bioelectronics, from Cork by way of Boston. Be nice to her, she's on a fellowship and it's paying for the coffee machine." Then she leaves, because Dr. Brack has never once stayed in a room longer than necessary.

Clodagh is, you have to admit, very pretty. Black curls pinned up with a pencil, freckles across a sharp nose, a wide gap-toothed grin she aims at everyone like a flashlight. Rafi sits up straighter. The undergrads stop pretending to work.

She aims the grin at you.

"You're the heat sensor man," she says. "Ethan, yes? Rafi warned me about you." "I read your paper on the trip down. The one with the shirt."

"The one with the shirt," you agree.

"I want to borrow your brain." She perches on your stool without asking, which leaves you standing. "I'm building something to read stress hormones through skin and it keeps getting confused by temperature. Lunch? I'll pay. I'm told you're poor."

"Who told you that?"

"Everyone," says Rafi happily.

Around her neck, on a thin silver chain, hangs a pendant: a teardrop of glass the size of a thumbnail, clear as water. You notice it because she plays with it while she talks, rolling it between two fingers. It catches the fluorescent light in a strange way. Not glittering. Glowing faintly, from inside, like a cold ember.

You have lunch with her. She asks good questions about your sensors and strange questions about your life. Where do you live. Bloomfield, nice, near the bakery? Live alone? Oh, a roommate, what's she like?

"Quiet," you say.

"Lucky you," says Clodagh, and her eyes don't move off your face.

You leave your laptop charger at home on Friday, which is a disaster, because your laptop is eleven years old and holds a charge the way a sieve holds soup. You're trying to remember if Rafi's charger fits when the lab door opens and every conversation in the room stops.

Nyx is standing in the doorway.

It's four in the afternoon. You've never seen her in daylight outside the flat. She's wearing a long camel coat over a cream sweater, her hair down her back like poured wine, sunglasses pushed up on her head. She looks around the basement with polite curiosity, as if she's visiting a ruin.

The undergrad at the oscilloscope drops a probe. Rafi actually stands up. A grad student from the lab next door, passing in the corridor, walks into the doorframe with a soft thump and says "sorry" to it.

Nyx doesn't notice any of them. She finds you, and her face does something small and warm, and she holds up your charger.

"You left this on the table," she says. "It was looking at me."

"You came all the way here?"

"It's a nice day." Which is a lie; it's drizzling. She crosses the lab, every head turning to follow her like sunflowers, and puts the charger in your hand. Her fingers don't touch yours. You notice that. She's careful about it. "And I wanted to see where you go all day."

"This is it," you say. "Glamorous."

"It smells like burnt pennies." She looks around, delighted. "I love it."

Then she turns, and you see her see Clodagh.

Clodagh is at the far bench. She hasn't moved. She isn't staring at Nyx the way the others are, dazzled and stupid. She's watching her the way you'd watch a dog you aren't sure about. One hand is closed tight around her pendant.

Between her fingers, the glass has gone cloudy. A faint, smoky blue.

Nyx's smile doesn't change at all. "Hello," she says pleasantly.

"Hi," says Clodagh. "You must be the quiet roommate."

"I must be." Nyx turns back to you. "I'll see you at home, Ethan. Don't skip dinner."

She leaves. The lab exhales. Rafi sits down very slowly and says, to no one, "Okay. Okay, I understand everything now."

When you look back at Clodagh's bench, she's tucked the pendant inside her shirt.

That night you lie in bed and stare at the wall and run an experiment.

It's not a good experiment. No controls, a sample size of one, the subject is yourself. But you've been thinking about it all day, and you're an engineer, and you need to know.

You think about her on purpose.

You think about her in the lab doorway, her hair dark against the camel coat. Her saying I love it about a basement that smells like burnt pennies. The careful way she kept her fingers from touching yours. You let yourself want her, just a little, like opening a tap a quarter turn.

On the other side of the wall, something goes still.

Then, very softly: knock. One knuckle against plaster, right about where your head is.

You stare at the ceiling. Your heart is going like you've run up Liberty Avenue.

You knock back. Once.

A long pause. Then two quick knocks, which you somehow know means stop it, I'm trying to sleep, and also means something else. You laugh out loud into the dark like an idiot.

Your phone stays dark. Neither of you texts. It feels like the wall is the conversation.

You get up for water around one. The kitchen is dark, and through the window over the sink you can see down into Cypress Way, wet and shining under the streetlight. A car is parked across the street. An old sedan, engine off.

Someone's sitting in it.

You lean closer to the glass. The man in the driver's seat is holding something in his lap. An oil lamp, old-fashioned, with a glass chimney, its little flame burning steady in the dark car.

The flame is blue.