The first time it happens they're on the tour bus, and Harry and Zayn are sprawled on the couch. Zayn's got his sketchpad out and Harry's on the phone, giving an interview to some morning radio show in Canada.
"So I hear you like to tell jokes during your concerts," one of the deejays says.
"That sounds like fun," the other one says. "Any you can share with us?"
"Um, let's see. Oh, I've got a two-parter. What's the difference between an elephant and a grape?"
Zayn stops drawing for a minute and looks up at Harry, who grins back at him.
"What?" the deejays ask.
"Grapes are purple. What did Tarzan say when he saw the elephants come over the hill?" Harry laughs, just a little. Zayn rolls his eyes and pulls Harry's left arm into his lap, leaning over it and writing something with the felt tip pen he'd been using to draw. Harry lets him, focusing on the punchline to the joke.
"'Look, here come the grapes over the hill!' Tarzan was colorblind."
There's a small silence over the phone before the second deejay says, "That was a terrible joke."
Harry just giggles at him. The rest of the interview passes pretty quickly while Zayn finishes writing and kisses his elbow before putting Harry's arm back in his own lap. After Harry hangs up, he lifts his arm up so he can see that under Harry's Things i can't tattoo, Zayn has written tell a funny joke.
"Hey," Harry protests.
Zayn shrugs. "Just telling the truth. Sorry, mate."
"What?" Niall asks, looking up from where he's been bent over his guitar. Harry holds up his arm for Niall to read. He laughs when he does.
"That is true," he says. Harry pouts and crosses his arms over his chest.
"Oh, wait," Zayn says, reaching for his right arm.
"Is this going to be something insulting as well?" Harry asks, even as he's letting Zayn take it.
"Nope," Zayn says, writing something quickly and releasing Harry's arm.
Things i can
Niall actually gets up to stand over Harry's shoulder and look at the new word, and then both he and Zayn are laughing, hard.
"I think you should get those tattooed," Niall says. Harry frowns, rubbing a finger over tell a funny joke.
"This is gonna come off, right?" he asks distractedly. Zayn licks his thumb and presses it to the words, smearing them.
"You might have to scrub a little harder, but it'll come off without any trouble."
He forgets to wash them until after all the boys have seen it and teased him for it, which means it happens again.
This time it's in a car on the way to an interview, and it's completely unprompted. Louis, sitting on the other side of Liam from Harry, just says, "Zayn, throw us one of your drawing pens, yeah?"
Zayn, sitting in the seat in front of them with Niall, narrows his eyes and says, "Why?"
"I'm going to write on Hazza's arm."
Zayn nods, and hands a pen over. Harry's holding his arm to his chest, looking at Louis suspiciously, but all Louis has to do is raise his eyebrows and Harry sighs and stretches over, laying his arm in Liam's lap so Louis can reach it.
Things i can't
wash my hair
and there's a little face drawn next to it with its tongue sticking out. Harry frowns.
"Yes, I can," he says.
"What's it say?" Niall asks, leaning over the seat trying to look at Harry's arm.
"It says I can't wash my hair," Harry says.
"It is proper greasy today," Zayn points out.
"Yeah, Lou's going to give one of those really deep, disappointed sighs when she sees it," Liam says.
"Lou loves me," Harry says.
"'Course she does, that's why she'll just sigh at you," Louis says.
Harry runs one hand through his hair in protest. "It's part of a whole look," he says.
Louis gives him this look, and Harry kind of shrinks into himself. "It is," he protests weakly, but the truth is that the look is I overslept and couldn't be arsed to take a proper shower and Louis knows it.
The whole thing gets dropped when they're in the interview, and Harry keeps his left arm turned over the whole time so no one can see what's been written. When they get out, Liam grabs his right arm, pen in his hand.
Things i can
give a proper interview!
Liam grins at him when he lets go, and Harry tackles him in a giant hug in the car.
It starts happening regularly after that. All the boys just take his arm at random moments: during business meetings, quiet moments on the bus, backstage before a show, early morning over breakfast. Caroline eventually starts dressing him in longer and longer sleeves, shaking her head every time she sees it but smiling a little anyway.
Things Harry can do vary from charm everyone (Zayn, after witnessing Caroline trying to hide a smile at Harry mere moments after she was admonishing him for getting pen ink on his shirt again) to play 18 holes under par (Niall, after one of their golf dates, accompanied by a big hug and a sloppy kiss to Harry’s temple).
Things Harry can’t do vary from find my key (Louis, one night at a hotel when Harry showed up at 2 AM, sheepishly explaining he’d been locked out) to kick a football (Louis, after yet another impromptu football game outside a venue and a disastrous attempt by Harry to kick the ball back towards him after it’d rolled away).
Harry tries to retaliate against Louis writing on his arm by playing a game of noughts and crosses on Louis’ arm, but even though he draws circles over the Xes, Louis just laughs and writes win at noughts and crosses on his left arm.
Harry’s starting to spend a lot of time with his left arm in Louis’ lap, actually. The rest of the boys mainly write under his Things i can tattoo, little reassuring things or to-do lists (Liam writes the majority of to-do list items, like wake up early for the morning show!!!! the night before an interview. Zayn’s favorite thing to write starts being wash me! with little smiley faces after Harry forgets to scrub the words off one too many times). Louis, though, only seems to write under Things i can’t, and though none of them are necessarily bad or mean, it starts making Harry wonder.
The rest of the boys are in Louis and Zayn’s hotel room one morning, room service trays full of breakfast all around them even as Zayn snores quietly under his covers, when Harry walks in, blearily rubbing his eyes and wearing only boxer briefs. He drops onto the bed next to Louis, who barely spares a glance at Harry before picking up one of Zayn’s pens and pulling Harry’s left arm into his lap.
“Isn’t it too early for this, Lou?” Harry asks quietly, but Louis just snorts and nods and keeps writing.
Things i can’t
wear proper clothes
Harry frowns at his arm when Louis flings it back at him. He’s spent the better part of three years not really wearing clothes and Louis has never seemed to care before. Luckily, the boys have stopped gathering around to see what’s been written on Harry’s arms anytime it happens (and Niall, who is always the most interested, is completely distracted by breakfast), so Harry can just quietly say, “What’s this about?”
Louis doesn’t look at him, but his cheeks get the tiniest bit pink, which Harry only notices because he’s watching him closely, staring at the side of his face like he’s done so many times before.
“Nothing,” Louis hisses. “It’s just a little…distracting.”
Harry is definitely not imagining the pink tint to Louis’ cheeks now. If he were anyone else, he might take the opportunity to tease Louis, but as it is, he just says, “Oh,” and gets under the covers next to him. Louis lets out a big breath, and after a moment Harry feels cold toes on his ankle. He smiles, and steals a piece of bacon off Louis’ plate.
Louis doesn’t start writing under Harry’s Things i can tattoo, but Harry starts to notice that Louis is usually either incredibly exasperated when he pulls Harry’s arm into his lap (make a perfect cuppa – “Honestly, Haz, you’ve known me how long and you still don’t know the correct ratio of cream and sugar, it’s a bit embarrassing by now.”) or too proud to speak (hit a wrong note with a huge grin on his face after a particularly good show).
Zayn tries to pull Harry’s left arm into his lap one day, and Harry blurts, “Not that one,” and gives him his right arm instead, awkwardly crossing it over himself to offer it to Zayn, who just raises his eyebrows and writes act really weird instead of whatever he was going to write.
That’s when Harry realizes that he’s basically just saved his left arm for Louis, and he starts dropping his left arm into Louis’ lap instead of waiting for Louis to pull it over. That earns him be subtle one day, but Louis’ mouth is twisted the way it is when he doesn’t want to smile but can’t quite hide it, so Harry considers it a win and conveniently forgets to wash his arm for two days.
They have a day off between shows and traveling in North America and spend the morning piled into Liam’s hotel room, quietly eating breakfast and teasing each other. Harry’s got a mouth full of eggs when Louis pulls his left arm into his lap, a pen in his hand. He takes his time with this one, and Harry lets him, eating his eggs with his right hand and watching as Liam tries to get up the courage to steal food from Niall.
When Louis finishes, he caps the pen with a flourish and very gently settles Harry’s arm back in his own lap. Harry looks at Louis and he looks kind of nervous, which makes Harry frown and twist his arm around so he can read it.
Things i can’t
say no to dinner?
with one of Louis’ big smiling faces next to it. Harry has to read it twice, infusing it with the meaning he knows Louis put into it – they’ve had dinner together thousands of times, but this isn’t dinner, this is dinner. He looks back up at Louis, who looks downright worried. Harry smiles, and Louis lets out a big breath and grins back, which makes Harry grin, and then they’re both laughing at nothing.
It’s only three months later that Louis finally pulls Harry’s right arm into his lap and writes:
Things i can
fall in love
Harry gets it tattooed on.