This is not the way he should be making an entrance.

When a man like this enters a room, a door should swing open—no, fly off its hinges—and the great wrecking ball that is him should lumber forth, laying waste to everything in its path. Fear and testosterone and handlers should whoosh in with this professional gladiator, this commander of multi-million-dollar contracts, this subduer of equally large men whom you now see galumphing toward you. At the very least, he should spit profanities as he enters, or beat his chest, or aim a preternaturally large paw menacingly in your direction.

“J. J.,” he says, shaking your hand politely. “Great to meet you.”

For a moment, you just gaze up, up, up at this six-foot-five, 295-pound mystery, wondering how many more times today your expectations will be confounded by the continent before you: its southern hemisphere of flip-flops and baggy shorts, a chiseled jawline straight out of Captain America visible in its northern climes, and north of that a size XXXL grey beanie shading much of the faraway country that is his forehead.

He sits down dutifully, as if still obeying some long-ago parental directive, and it’s only then that you realize how much he is a creature of his 24-year-oldness: alternately funny and sincere, engaged and distracted, happy to be living the NFL dream yet still young enough to be surprised by the trappings. There is confidence in his eyes, but also fear, which reminds you of something a guy told you on the way to the press room, deep in the bowels of Reliant Stadium. What was it he’d said? Something about J. J. being different. Something about J. J. playing “scared.” Not scared of opponents—scared of losing his edge, scared of losing his job if he lets down his guard. A man needs fear like that, you think, if he’s going to hit the weight room at 5:30 a.m. most mornings.

He’s at the superstardom-as-work-in-progress stage, when everything seems unreal and everything happens too quickly. He has only just broken the Texans’ record for sacks, only just played in the Pro Bowl as the AFC’s starting defensive end, only just been named the AP defensive player of the year.

Only just finished his second season.

There are people who think that J. J.’s on-field accomplishments are attributable to a singular ferocity that is itself due to a killer instinct, a storied “beast mode,” and serious anger issues. The great ones always hate, they say. But then you sit across from J. J. and it becomes obvious that those people are full of it.

“Nah, I’m not angry, I don’t hate ’em…. Ninety-nine percent of the time I don’t even know them.” He says this so casually, so reasonably, for a moment you forget that a person doesn’t have to know someone to hate him. “It doesn’t help me to hate the guy across from me. There’s no advantage there.”

You say nothing, you have no comeback. You are busy daydreaming about what sort of horrible carnage this man might inflict if he actually did hate someone, but then the subject changes to … his charity work. The J.J. Watt Foundation, which dates back to his junior year at the University of Wisconsin, is devoted to funding after-school athletic programs for kids in low-income areas, both in Houston and his home state (also Wisconsin). As J. J. rattles off some convincing research that connects such programs to improved classroom performance, he displays the same vehemence you see in those YouTube videos of him in the Texans’ weight room.

“I never, ever want to be that athlete where you look into his foundation and it’s being run the wrong way for the wrong reasons,” he tells you. “I believe in my foundation. I believe in what we’re trying to do. And I believe in doing things the right way.”

Why kids, you wonder? J. J. seems to have wondered the same thing. He thinks about it a moment, then tells you that the more the adult world hits him with demands and hosannas, the more the world of children becomes a kind of refuge. He doesn’t say it, but you get the sense that what J. J. Watt is craving, even more than football glory these days, is honesty. For him, kids represent a kind of last stand for realness in a world swiftly being taken over by fakes.

“Whatever kids are doing at the time is the most important thing in the moment, and that’s what’s cool to me,” he says, talking like a man who had no childhood, instead of a Field of Dreams one in a place called Pewaukee, population 13,200. “The only thing they’re worried about is having fun. In such a structured, business world, it’s fun to get away and relax.”

At this point you carefully and politely note that he is a 24-year-old millionaire and, as such, might be out there carousing with groupies, making frivolous purchases, speeding down the road to ruin in advance of a well-orchestrated, feel-good comeback.

It is the special genius of J. J. that you feel like a complete dumbass saying such things to him. He looks almost worried for your sake, as if the world dodged a bullet when it decided to grant him rather than you this life, although “granted” is hardly the right word for a kid who’s been striving for this moment since nursery school. He ticks off the high points of the elite athletic timeline: the hockey kid who always wanted to make the most goals, the youth quarterback who wanted to score all the touchdowns, the seventh-grader who wrote, on MySpace, of his desire to someday meet Roger Goodell and be drafted into the NFL, the ninth-grader who practiced his autograph incessantly, and on and on.

In other words, he’s been working toward this life since way before he knew it would mean unwanted attention and endless interviews, before he knew he wouldn’t be able to drink alcohol or have the typical social life of a twenty-something. Still, the sacrifice was worth it for this, he says, this being not fame or fortune but the growing consensus that he’s the best in the world at what he does.

“I live my life dedicated to this game,” he states. “I’m not married. I don’t have kids…. I sacrifice fun, free time, but so far it has paid off.”

It helps that he seems to have little taste for the high life. Not for him the weekends spent living it up, the quick jaunts to Vegas, the nice cars and enormous houses. Paradise for J. J. means a comfortable home in Pearland, surrounded by the public. He doesn’t need to “validate” himself with a big house or a Ferrari, he tells you, and somehow you believe him.

Which is not to say that his life hasn’t changed, of course. Like many a sports star before him, he’s grown more insular. He’s had to hire someone to pick up his mail and do his shopping and run his errands. Increasingly, he comes home at night to fans camped out in his driveway, forcing him to consider “gated communities,” words he utters with all the affection one might feel toward a concentration camp. He doesn’t go to restaurants because that would require calling ahead and slipping through the kitchen to avoid causing a stir. And so here he is most nights, whipping up dinner for one in Pearland, zoning out with a little TV before rinsing out his plate and tumbler and hitting the hay at 9:30.

“I’m very outgoing and I do a lot of things, but I don’t need to go to fancy restaurants, I don’t need to go to bars,” he says, not defensive in the least. “That’s not who I am. I’m more of a stay-at-home, Midwestern-type kid anyway.”

You tell him that you find this description of a professional athlete’s life to be disturbing and almost absurdly unglamorous. Surely there must be some portion of the fantasy that conforms to expectations. Women? Dating?

J. J. shakes his head and looks down with a sympathetic smile. You still don’t get it.

“There always seems to be something in it for them, whether it’s the fame, tickets, money,” he says. “I basically have to either know somebody that I already trust or it’s somebody that I’ve already known in my life. My circle of trust is so small, but it’s so strong.”

The circle he speaks of seems to consist mostly of his immediate family: his two younger brothers, both of whom intend to follow J. J. into football, his mother, who was vice president of a building inspection company until quitting last month to take over the J. J. Watt Foundation, and his father, a Pewaukee firefighter.

It’s this last member of the circle of trust who’s most on his mind this day. His dad’s a firefighter, after all, as is his uncle, and the previous afternoon J. J. had attended a three-hour memorial service at Reliant in honor of four firefighters who’d given their lives on the deadliest day in the history of the HFD. He wasn’t the only one there. Most of the Texans’ roster was in attendance too. But it was the hulking blond guy in the black suit that caught your eye.

There he was, lagging behind the rest of his teammates, shaking the hands of awestruck firemen and offering condolences to the victims’ families. It wasn’t the gesture that stood out for you, it was that face again, J. J.’s face, a face that in one setting spells danger and destruction, but in another signals only a 24-year-old scared and saddened by the world he’d grown into.

Even from a distance you could see the lines in his face, the anguish carved into it. Was he thinking about his father when he was shaking all those hands and fumbling for words that might console?

Absolutely, he says, especially after listening to the families of the fallen firefighters, their stories of loss. He found such tales painful to hear, he admits, but also important to hear, for a whole host of reasons.

“It had never really registered with me that my dad and my uncle are firefighters and there’s the possibility of that being my mom or my family losing them.” He pauses a brief moment.

“It felt very real.”

But for the time being there are more pressing concerns: film to watch, calories to consume (9,000 a day), and the perpetual struggle to unlock what remains of his body’s dormant power. In 2011, J. J. shocked YouTube viewers when he posted a video of himself jumping, without taking a step, onto a 55-inch box. These days, he’s aiming for 60.

He gets up from the table, says goodbye and strolls toward the door. A Texans staffer returns the stack of magazines he was carrying when he arrived, including a DuPont registry, the upscale buyer’s guide.

“Give me my magazines,” J. J. says, playfully grabbing the stack. “I’d like to see what it would be like to live like the rich and famous.”

He’s joking. But only sort of.

Web exclusive: read our full interview with J.J. Watt!