I think the question was "I'm thinking about writing something about them, so was tying him up a common occurrence?"
Luckily this is the one question of the night I wrote in Notepad instead of in Tumblr, because it got so long that I wanted more room to work on it.
Before I answer this (because I know this is gonna get long—hey, this is me we're talking about), I want to start with two things:
1. This is my take on the situation, but it doesn't change anything. Everyone's free to interpret the characters how they like and do with them as they wish!
2. It is not my intention to offend anyone with anything that's said in here. People like what they like, and need what they need, and experiment with things that interest them, so on and so forth. That's healthy and normal and fantastic! But the men we're about to talk about are not at all healthy, and the attitudes I'm trying to explain in this (never-ending) ramble are theirs.
Here's the two-sentence version of my answer:
I never considered it to be an ongoing thing with them—I just saw it as the final evolution of their trust.
And the essay longer answer ya'll knew was coming:
It's not something I would say is a common occurrence, no. But because my answer is no I want to explain why it even made an appearance in another Ask and why my answer is what it is.
Eventually Andrew will understand that it's okay to tie Neil's hands out of the way once in a while, but I can't see him doing it with any real frequency. Neil is the first person in Andrew's life who is allowed to touch Andrew, so tying him up cheats Andrew out of something he has never before been able to have and enjoy. Getting from where they are in King's Men to where they are after Nicky's wedding takes a lot of work and many years.
Let me see if I can make this make sense.
Roland makes good on his joke and gives them a pair of padded cuffs. He waits until the end of the summer, because the first half of the summer the Foxes are struggling with Aaron's trial and six new faces on the court. But in August he gives Neil a box and tells Neil to open it when he's alone at Fox Tower. I forgive him—he means well, he is just so happy that Andrew finally found someone who will stick with him, and he knows firsthand how much Andrew loathes being touched.
So yeah, they're partially a joke, but they're partially a "Go get 'im, friend!" show of support. He doesn't know any better, and luckily for him Neil and Andrew are too bruised by the gift to ever tell him what they honestly think of it. ((Andrew tries to throw the cuffs out the closed window of their dorm room. Luckily they're not heavy enough to break the glass, just crack it. Matt replaces the window when Neil asks him to but never gets an explanation as to what happened.))
Here's the thing ((that ya'll already know)): Andrew is an untrustworthy ball of issues and he & Neil still have a lot to work on when King's Men ends. But Andrew trusts Neil to stop if he says stop, and he trusts Neil to keep his hands to himself if Andrew's not comfortable with Neil reaching out for him. Neil knows and understands and respects the fact that a Yes today is not a Yes tomorrow when it comes to Andrew—today Andrew might let Neil put his hands on his back, and tomorrow he might push Neil's hands away, and Neil knows it has nothing to do with him in the end. It is about a comfort zone that has been breached too many times and Andrew learning what he is and isn't okay with.
Andrew tells Neil at the end of King's Men that he knows Neil can respect that about him, so turning around and tying Neil's hands feels like a "Just kidding, I don't fucking trust you" as far as Andrew's concerned. It turns Neil's "I trust you" into "I trust you, Andrew, but it's okay if you don't trust me enough in return." It turns Andrew into the men who pushed him down and wouldn't let him fight back. Andrew won't—can't—become that person.
And honestly? At this point in his life it's not much easier for Neil to consider such a thing. Until Andrew came into the picture, Neil always ran, because he knew what would happen to him if he was caught. Well—he was caught, twice, and as he always expected and feared he was brutalized to the point that he almost shattered. The last two people to cuff him were Riko and Lola, and they hurt him so badly that his wrists scarred from how fiercely he fought to get free. Maybe the loops around his wrists aren't as impressive as what Lola left on his knuckles and arms and face, but those lines are there. So really—neither of them is in any position to just tie the other down anytime soon.
But Neil keeps the cuffs, because he's getting pretty good at figuring out what Andrew's issues are and he knows this is something they're going to have to address at some point considering how angrily Andrew reacted. He tells Andrew that Nathan's trial is going to happen sooner or later and that he's rusty on his lockpicking when it comes to getting out of handcuffs. It's the thinnest excuse in the entire world but Andrew lets him have them, and Neil locks them away in his safe where Andrew doesn't have to see them again. They stay there for a long time, shuffled aside anytime Neil needs to get money out of his binder and never lingered over.
They don't make a real appearance again until Kevin's fifth year. It's Kevin's last season with the Foxes and this is where Neil really has to face the fact that he's going to be losing them. The upperclassmen left, and now Matt and Kevin are heading towards graduation, and that means the cousins will only be a year behind them. So Neil is a little on edge all this year—doesn't help that he and his vice captain don't particularly get along.
((Jack is very, very good, and very smart, but Neil and Jack had serious issues for all of Neil's sophomore year. They're better this year, but better is always relative when it comes to these two. Granted, Andrew doesn't help things by calling Jack "John" instead of Jack))
((In America, "Jack" is a legitimate nickname for "John", so Andrew's not wrong by calling him by his birth name–he's just an asshole for refusing to respect Jack's choice to not go by John. Childish spite, thy name is Andrew))
Late that fall the Foxes head to Eden's Twilight to celebrate a win against USC. For clarification—there are two USCs in the United States. 90% of the time everyone's referring to the one you all read about in the books—the University of Southern California where the Trojans play. For years I insisted that USC was an imposter, because there is also a University of South Carolina. In this instance, we are definitely talking about the one in South Carolina—which happens to have its main campus in Columbia.
The Foxes show up at the club to have a good time, but halfway through the night they bump into some players from USC's team. It's a pretty heated interaction because both sides (save Neil & Andrew) are wasted. Kevin says something really rude, Neil's feeling salty enough to back him up, and the argument becomes an all-out bar fight in a heartbeat.
Security breaks up the fight, but someone's already called the cops, so the lot of them are cuffed and hauled away and tossed in the drunk tank to cool off overnight. Andrew, being Andrew, picks free of his cuffs before the police have a chance to do it for him. Neil remembers the pair he locked away that he swore he'd practice with but didn't. The next week he finally digs them out and starts slow, locking one wrist at a time. It annoys him having the second cuff dangling free, though, so he cuffs himself to one of the beds. Andrew finds him working on it later.
They argue for a while, Andrew poking holes in Neil's methods and then tolerating Neil's frustrated rant over the day's Exy practice. Neil keeps working while they're talking and eventually thinks he can tackle two wrists. This is more of a pain than he honestly expected it to be, because his hands don't want to move the way he wants them to, and after a couple botched attempts Neil gives up and just talks so Andrew won't notice and comment on how useless he is. Andrew notices, but he waits until it's time to eat before saying he's not letting Neil out. Neil got himself into this mess, so he can stay here and starve while the rest of them get dinner.
Neil manages to get free while Andrew's away, but he gives up on his practice for the night. The next day Neil cuffs himself to Andrew so Andrew can't leave him behind again. Andrew is pretty sure that defeats the entire purpose of the experiment, but he doesn't break free.
Neil does figure it out after enough practice. And this matters, even if they don't yet fully recognize the significance. Neil can get free if he wants to be free. It is not a green light, but it is important.
The green light, if it can be called that, is when Stuart Hatford is murdered, traded out for a younger, more ambitious successor. And Neil didn't really know him but Stuart was family, was the only relative he had left in the world, was his mother's brother. He hears the news long before any of the Foxes do; one of the Moriyama thugs gives him a heads-up before it happens because they need to know if his reaction is going to be a problem. Neil doesn't agree and doesn't want this but he's not in any position to do anything about it considering he's already signed away his life to Ichirou.
And Neil does what Andrew told him not to do—he starts something when he knows his head's out of sorts. At least he's smart enough to warn Andrew ahead of time, as he presses the handcuffs into Andrew's uncooperative hands and kisses his words into the line of Andrew's jaw. I'm not in the right place to know where the lines are with you, but I need you right now.
A few years ago Andrew never would have let Neil get away with this, but that was then and this is now, and Andrew's coming to terms with the idea that Yes is always yes unless I say no. So he takes the handcuffs Neil gives him and pushes Neil down. His questions can wait until tomorrow; what matters right now is that sick gleam in Neil's eyes that looks a little too much like Nathaniel.
It will be a while before they do this again, and next time it won't be tainted by emotional duress, but one day they're going to be okay. One day they'll have come far enough that Nicky can hand Neil a garter as a joke, and Neil will show it to a not-amused Andrew at their hotel room and ask Was I supposed to throw it back at him on his own wedding day?, and Neil will pretend like he's going to put it on Andrew and Andrew responds by tying Neil to the headboard with it. And neither of them will think too much of it, because they have evolved past the point where this could have been a problem.
I won't say it's the last time they do such a thing, but I've never wanted to consider it past this point. I'm interested in their milestones and how they get to each one. This milestone didn't exist until I cut out some pretty ugly events for the final rewrite. I wanted to know if taking those pieces out changed certain things, like whether or not they could be okay with little games like these, so I mapped a path to this point. I learned what I wanted to learn about them and I'm happy leaving it there.
But refer back to #1 at the top! My take on things does not have to be your take on things. I want you to have fun, whatever you do! Go forth and write with my blessings. :)