The first week of term is about getting settled in. Art college is even better than I hoped, with its workshop like studios and people just like me, who are passionate about art and don't want to do anything else. But the functional spaces aren't as romantic as the lawns and quadrangles of Trinity, and we don't have our own bar on the premises.

The Buttery has an innocuous entrance off one of Trinity's main quadrangles. Last year I often skipped school to meet Spike in here. It had an illicit charm, drinking at 10 am on a student campus when you were supposed be in school. It's pure fantasy the way banal concrete steps lead unexpectedly into another world. Beyond a mundane 1970s door, a dimly-lit medieval basement with low-vaulted ceilings, stained yellow with generations of nicotine, awaits discovery. Despite the dark jaded walls, that must have heard all there is to hear down through the years, the Buttery doesn't smell like other bars. It has a distinct odour of youth, full of zestful energy and exuberance, with a top note of hope and a base of despair.

Spike is waiting for me in a corner alcove. It's only when I'm right up close, I recognise the guy in the beanie sitting with his back to me and my heart sinks. It's our first weekend together and I'd hoped it would be just the three of us. In fact, it never even crossed my mind Tully would be here, but he's leaving soon so, no matter how much I want to, I can't really complain about him trying to spend as much time as possible with Kit before he goes.

"How's the struggling artist?" Spike deposits his Guinness on the black table in front of him and rises to hug me. "Any creations to show us?"

"Have a look at this!" I toss over the pendant I made this morning.

"It's great, I didn't know you made jewellery in art college?" Spike fingers the gothic letter F, with its black enamel gloss.

"We don't really. It's just a short metalwork module and today we did enamelling techniques. Vincent, the teacher, really liked this. He showed it to the whole class and said I had an eye for design and had picked up the technique really well."

"Wow," Tully takes it from Spike and passes it back to me, "that's really good."

"Yeah, thanks." I shove it back in my bag, unreasonably disappointed that neither of them are interested in hearing about my visions of a whole alphabet in silver and black, or maybe even initials entwined. I turn to Tully, "Didn't expect to see you here, aren't you afraid of being recognised?"

Nobody is paying us the slightest attention. Even if they knew Tully Cabe was sitting here in this corner, the blasé literature and philosophy students who frequent this place are way too cool to admit they care. But my sarcasm is wasted on him.

"Spike warned me to wear black," Tully replies with a smug smile. " And he was right. It's so dark in here, I blend in perfectly."

"Do you want a Guinness to match the decor?" I ask.

"No, I'll just have a coke, please."

Shaking my head, I make my way to the bar and catch sight of a figure hovering tentatively in the doorway.

Kit! I wave over at her and her face brightens into a smile as she comes over to join me at the bar. "What is this place?" she asks looking around at the vaulted arches.

"I think it's a basement."

"Yes, it has an underground feel to it."

A memory of the prehistoric passage grave at home flashes in front of me. It too has a vaulted underground chamber but the entrance is locked and barred, so we have never been inside, but my thoughts are interrupted as Liz Quinn rushes over and buries Kit in a cashmere and Chanel No 5 scented hug.

"You got law, right? I did too. Imagine we're going to be here together, isn't that incredible?"

I snort into the pint the barman passes me as Kit throws me a despairing look over Liz's shoulder.

"It's so great to see you guys. Who are you here with?" Liz asks.

I say nothing but Kit glances involuntarily over at the table where Spike and Tully are sitting.

"Wow, that's not Tully, is it?" She falters and it's the first time I've ever seen Liz Quinn stopped in her tracks. She has no idea how to approach him now he's a celebrity. But she doesn't remain at a loss for words for long.

"Tully!" she screeches, bounding over to the table, "is that really you?"

Kit stumbles after her, pale as a ghost. "Liz is doing law too," she tells Tully.

"Hey, that's great, you'll have a friend here." He may be famous, but Tully is as oblivious as ever.

Liz almost melts into a swoon as she replies in a breathy voice. "Don't worry, I'll look after Kit. We go back years."

To be fair, Liz doesn't bother me as much as she does Kit. Mostly I think if Mrs Lawless hadn't insisted on foisting them together as kids they'd get on just fine, but this is one of those moments where I can totally see why Kit finds Liz Quinn so annoying.

Moments later, the table is surrounded by a crowd of enthusiastic undergraduates eager to meet Tully. So much for the cool students drinking Guinness to match the scarred black and cream decor, they are just as star-struck as anyone else. Finally, I understand why Tully never wants to go out.

Kit is mortified, stuck on the edge of the gang mobbing the table and I beckon her back to the bar. "You haven't a hope of carrying out a rescue. You may abandon him to his fate."

"I feel so bad," she says, "like it's my fault. I should have known better, but he really wanted to meet us here. He was so curious to see what being a Trinity student is like."

"They don't usually act like that!" Spike has managed to escape and join us.

"It makes me feel invisible," Kit goes on, "like no one will ever see me when he is there."

"You don't mind, do you, that he's doing so well?" Spike asks her.

"It's strange, I used to want it more than anything. Last year, when he was stuck in Drimshanra and it seemed like such a dead end, all I wanted was for him to get out of there, do something with his life. But now that he has, I don't know, I suppose I feel left behind."

"Don't worry, Tully only ever has eyes for you, Kit!" It's true Tully adores Kit, but she has a point. Nobody could ever have anticipated this level of success. Perhaps she is right to be worried at the cost of so much fame.

"He's taking me to Paris next weekend," she says.

"No way, that's so romantic!" How come she hasn't mentioned it before? "When did you find out?"

"Yesterday, it's a birthday surprise."

"But it's not your birthday till November." Too late, it dawns on me. Tully won't be here for Kit's eighteenth birthday. He'll be in the middle of the tour. "That's an amazing surprise, you've dreamed of going to Paris for years!"

"Yes, I know, but I'm sure it means he wants to tell me something. Supposing it's bad news?" Kit looks down, unable to meet our gaze and that's how I know she's genuinely worried.

"Tully wants to spend time with you, just the two of you, before he leaves." Spike rushes in to reassure her and it seems to work.

"God, I can't even remember when the last time we did that was," Kit says. "Sometimes I wonder if this is all my fault?"

"No, Kit, how could it be? You didn't sign up for this." It hits me how hard all this is on her. "You could never have expected any of this to happen."

"What about Aonghus? Even though I've tried to tell myself the pact with Aonghus doesn't exist, even though there's a part of me that believes that, another part of me can't help thinking that music is taking Tully away from me. He doesn't need me any more and I'm just left here, on the sidelines."

"Kit, Aonghus isn't real and Tully isn't choosing between love or music. He has both. And now he wants to spend time with you." But she shifts away from me, looking down, avoiding my gaze. She's not buying it and, looking over at Tully enthralling a crowd of under-graduates, growing in confidence and charisma before my very eyes, I can see why Kit is worried.

"We need to get him out of here." Spike gestures at the table where Tully has almost disappeared into the crowd milling around him.

"Fine!" I elbow my way in, grab hold of Tully and pull him out.

When we emerge out of the crowded bar into the cool evening air in the spacious quadrangle, the four of us erupt in gales of relieved laughter.

"Woah," Spike gasps, "that was intense!"

"So much for blending in," I can't resist commenting and we all laugh even more.

"Girls!" Tully pulls us both close. "We have some news."

"Guess what!" Spike's voice is gleeful. "Tully has invited me to go to America with the band as a journalist to cover the tour."

"What?" Kit's eyes are wide and horrified. "Seriously? When did this happen?"

"Just there now, in the Buttery, before you turned up and unleashed Liz Quinn and her minions on Tully!"

"Are you going?"

"Of course, I'd be stupid not to," Spike says. "It's a once in a lifetime opportunity. Imagine Four breaking into America!"

"But you have to give up your studies and leaving Trinity is a huge risk. Are you sure about this?" Kit says and I get where she's coming from. Without Spike, she'll either have to face Trinity on her own, or accept Liz Quinn's support, so yeah, she's not happy.

"He doesn't have to decide straight away," Tully says. "He can take a week to think it over."

"But I don't need to," Spike replies, "my mind's made up. When a door opens you have to go through it, because you could be knocking a long time before it opens again."

"Spike's right," I nudge Kit. "It is an amazing opportunity."

She takes the hint. "Yes, of course, congratulations Spike!"

But her eyes are shot with misery and I can't help feeling sorry for her. No matter how achingly beautiful the quadrangle is in the semi-darkness, Kit is going to struggle in Trinity without Spike.