TBH if you've got a 14 year old transvestite as you mc you probably don't need to introduce a load of 50 shades stuff as well Homer - I assume he means tying each other up during sex
Why are they tying each other up then? No snark intended, I'm just confused as to the motivation behind playing this game, which could help answer your question,
It's a bit of fun between the teens kind of where they challenge each other to escape from their bonds
You can do almost anything in a teen book these days. If it's not sexual then you have no problems at all. Trust me, there's a lot worse in my books and no-one's ever had a problem with any of that. Especially if there isn't even the hint of it being sexual then it's not even a worry.
Is this something teenagers actually do for fun? Honestly asking - I've just never heard of it before.
Depends on the kids and the world. I presumed that it was some fantasy thing where they were thieves or assassins or something, or circus performers or lots of stuff really. Even just kids who are kinda weird and into escapology and lock picking and such like might do that. I would agree that in a contemporary setting with reasonably normal kids you'd need a strong reason for them to be doing that but I don't think it's out of the question.
Seeing the other responses, I have a question. If it's completely non-sexual, what is it about it that you think is a problem? Is there something about it that is especially risky? Are they tying someone up and then throwing them in a pool? I don't see why (based on what you've said) there would be any question of a problem, so why do you think there would be?
Your brevity is admired, but I'm afraid I need more info. Needs to be done the right way... how? Need to describe the knots the right way? Need the kids' reactions to be authentic? Need to make sure it serves a purpose? Need to make sure the rope will hold up properly? Need to make sure they really wouldn't die (or really would)?
Your brevity is infuriating @MrInvisible Sorry to put it so bluntly, but I feel like we're playing mother-may-I here. Please explain the full scope of your question. What are the tie-up games you describe, how will they be used, why are they important, etc. We can't help you if we have no idea what you're talking about. We see tie-up games and we think hardcore fucking.
Devil's advocate here, maybe, but if it's not a sexual thing, then it actually sounds like something I used to do as a kid (as in, pre-teen). We were really into escape artists like Houdini, and I'm technically double-jointed - albeit not in one of the cooler ways - so it was great fun for weird, bored kids. But, caveats: 1) If this isn't pertinent to the plot, eg a character gets kidnapped but they're able to slip out because they've got experience with it, then why include it, and 2) If you feel you need to ask this then I suspect there is a fetish / age-inappropriate aspect to this and you know it.
The last bit sums up my question, how do you write it so that it looks like they're having fun rather than it sounding sexual
You still haven't told us why you need it in the book. That's probably necessary for answering the question.
OK, your question is essentially un-answerable. If you want answers, you're going to have to make it answerable by answering some of the questions that people have asked.
I guess I'll reiterate - are they interested in escape artists / magic in general? Is there sexual content in the story at all / chemistry between the characters involved? I think it's your phrasing and the fact that you're asking at all that's made people's minds go to bondage. If you treat it as nonsexual hijinks that the characters just find amusing, then I think it'd probably be fine. When I was a kid it was a passing hyperfixation on escape artistry. I could absolutely see idiot teenager Izzy also getting into it just by seeing something about Houdini on tv, sitting bolt upright, and going, "I bet I could totally do that shit". Portray it as a challenge or an oddball interest or something like that.
I intend to treat it as non sexual hijinks between my teenage character with maybe a bit of help from their parents/guardians