At first, Gene Simmons gives off a rough-and-tumble vibe. “I was a bad guy,” admits the KISS frontman of his rock star lifestyle. But it’s clear from the video tour that the musician gave to Us Weekly, Simmons has become a family man at heart. The 68-year-old rocker married former Playboy Playmate Shannon Tweed, 60, in 2011 (after dating since 1975), and gushes openly about her being “the heart and soul” of the Simmons clan, which includes the couple’s kids Nick, 28, and Sophie, 25. “She waited for me to get rid of my self-absorption and self-aggrandizement,” he says. “Until I grew up.”

Simmons has lived in the three-bedroom, 10-bathroom home “for a good 28 or 29 years,” he says, and everything in the space has been tailored to the family members’ “bigger than average” heights. “I’m 6-foot-2, our son is 6-foot-8,” he notes. “So this looks like a normal-sized table, but it’s actually bigger than people expect. The couches are taller and all that.”

While Simmons is often on the road working on his myriad projects (two bands, books, a forthcoming magazine, a film company and a restaurant chain), he relishes returning to the 16,500-square-foot Beverly Hills spread he’s lived in for nearly 30 years because it’s where he feels most himself. (His favorite spot: the man cave.) “To me,” he reflects, “home is family.”

The musician says that part of what keeps his brood grounded is the rules he and Tweed put in place. “We’re a very strict family,” he says of raising his two kids. “There’s no drugs, there’s no booze. You’re charming, you’re kind. That’s your job.” And though his two adult children have moved out, they’re still around on a regular basis. Jokes Simmons, “Shannon really has empty nest syndrome, but we force them to come over.”

Even when the kids are elsewhere, it’s a full house. “Lots of things happen on this property,” says the Israel native, who recently hosted a friend’s wedding since the home is where the couple met. His living room in particular, he reflects, “invites all sorts of interesting people to come by. There’ve been at least two heads of state.”

But Simmons doesn’t just welcome visitors in social situations. His home also acts as the headquarters for many of his business dealings. The bass guitarist estimates that he stocks his home offices with about 40 percent of KISS’ 5,000 pieces of licensed memorabilia — an impressive array he uses as his “home court” advantage. “All of this stuff is meant to disarm people,” says Simmons. “They go, ‘I gotta be in business with this guy. Look at all this stuff.’” One of his latest additions is ‘The Vault,” a box set that weighs a hefty 38 pounds. “If I tried to pick it up, I’d have to use two hands. Hardcore stuff.”