There's a type of person I keep hearing about in Japanese offices, and he always runs the same play.
He looks around the floor, finds the employees whose visa is tied to the company, and quietly hands them the heaviest load. The ugliest tasks, the impossible deadlines, the work nobody else wants. Not by accident. On purpose.
And he isn't shy about why. He'll tell other coworkers, out loud, that the foreigners can't really complain. If they lose this job they might not find another in time, and then they lose Japan. So they'll swallow it. He treats their visa like a leash.
Some go further. They brag that a foreign worker "can't defend himself." Push back too hard, the logic goes, immigration gets dragged in, and you're the one who ends up deported. He acts like that makes you powerless.
Here's the thing he gets wrong.

Read his strategy again and you'll notice it only works under one condition: you have nowhere else to go.
One job. One income. One visa sponsor. No other offers, no network, no one who knows how the system actually works. Strip away the bullying and what he's really exploiting isn't your nationality. It's your lack of options.
His power is your isolation. Take that away and the whole bluff collapses. A foreigner with three other companies who'd hire them tomorrow does not flinch when someone hints they're replaceable.
So the question that actually matters isn't "how do I survive this guy." It's "why does this one job have so much power over my entire life here?"
The threat about immigration is a small truth wrapped in a big lie.
The small truth: throwing a punch, literally or figuratively, is a trap. If you blow up, get aggressive, or hand him a real dispute, yes, that can get messy. He's counting on you being angry enough to give him exactly that.
The big lie is that those are your only two options, take it silently or explode. Don't fight on his terms. There's a third lane he never mentions, because it's the one that actually scares him.
Power harassment is not legal in Japan, and a work visa does not delete your rights. There are free labor consultation lines, your company likely has an HR or compliance channel, and you're allowed to document everything quietly while you line up something better. Changing employers on a work visa is normal. You notify immigration, you don't lose your status for switching. The leash is a lot shorter in his story than it is in real life.
Let's be honest about why it still feels impossible to walk away.
It's rarely the visa paperwork itself. It's that for a lot of people, this one company is their entire Japan. The job is the income, the routine, the only daily human contact, the reason the apartment exists. Lose the job and it feels like losing the whole country.
When work is your only Japan, you'll tolerate almost anything to keep it. That's the real cage, and a guy like this can smell it. He isn't betting on your visa. He's betting that you have nothing else holding you here.
Which means the most powerful thing you can build isn't a sharper comeback for the next meeting. It's a life that doesn't live or die by this one company.

Look at the foreigners who never end up on this kind of guy's target list. It's not that they're tougher or more fluent. It's that they aren't cornered.
They know other people in their industry. They've heard how someone else changed jobs and came out fine. They have a friend who's been through a visa transfer and can walk them through it. They have a weekend that has nothing to do with the company, and people in it who remind them they're a whole person, not a job title with a residence card stapled to it.
A network is quiet leverage. Every real connection you build outside that building shrinks his power a little more, because each one is a reason you're not trapped, and an exit you didn't have before.
You don't beat this kind of person by winning an argument. You beat him by no longer needing the thing he keeps threatening to take.

Here's the honest gap. You can understand every word of this and still be alone in a city of millions, which is exactly the condition that makes the leash work in the first place.
That's the part SewaYou is built for. It's a map-based app that shows you who's actually near you and open to meeting: other international residents who've lived through the same visa fears, locals who genuinely want foreign friends, language exchange partners who'll trade an hour of Japanese for an hour of your language. The people who turn "this job is my whole life here" into "this job is just one part of it."

No coworker should get to treat your visa like a leash. The surest way to make sure no one ever can is to build a life in Japan that's bigger than any single office, full of people who'd notice, and have your back, the day you decide to walk.