NY- He was hot for the teacher – and, understandably, lukewarm on conversation.

That’s what steamy perv teacher Debra LaFave tells NBC’s Matt Lauer about the “very flirtatious” middle-school student she first infamously seduced on her classroom couch in Florida in 2004.

“You know, there was very little conversation, to be honest with you. You know, looking back, he was 14. You know – what is there really to say to a 23-year-old?” LaFave says of her victim – to whom she eventually gave illegal sex-ed lessons in the back seat of her silver Isuzu Rodeo Sport as the kid’s cousin drove around aimlessly.

In her first TV sit-down, set to air tomorrow on NBC, the buxom, bottle-blond babe, now 25, admits to Lauer that she “crossed the line that never should have been crossed.”

But “I think he just became very flirtatious, and you gotta remember that at that period . . . in my life, I didn’t feel like an adult. I was crashing fast,” says the disgraced instructor, who cites bipolar disorder in a bid to explain her seamy actions.

“I don’t want to blur the lines between doing something as heinous as what I did and being bipolar. But, yes, symptoms of bipolar definitely contributed to my frame of mind,” LaFave insists.

The temptress teacher – who once seductively posed in a leather bikini and white high heels alongside a motorcycle – was married just three months when her torrid affair with the young teen began at Greco Middle School in the Tampa suburb of Temple Terrace in June 2004.

The young reading student has said he and LaFave started their relationship after she began cooing to him that “she had feelings” for him and “didn’t know what to do with them.”

The pair first shared a steamy sex tryst on a Monday, after LaFave asked him to help her clean out her classroom-trailer.

The boy said that as he sat on the couch, LaFave suddenly appeared in sexy, black, terry-cloth shorts and a thong and asked him if he wanted to have sex.

She wound up performing oral sex on him.

The panting pair had four more wild sex sessions over the next three days: once in the townhouse she shared with her unsuspecting husband, Owen, and three times in the back seat of her SUV.

Their last romp occurred that June 17, after the teen and LaFave drove halfway across the state to Ocala, where his 15-year-old cousin lived. At the time, “my cousin drove us around again and again [and] we had sex” in the back seat, the boy said in a police statement.

LaFave was busted after her young lover’s aunt spotted the pair in Ocala and told his mom. LaFave eventually pleaded guilty to lewd and lascivious behavior in the explosive case.

But she managed to dodge prison time after her lawyer told the judge that putting his comely client behind bars would be like “putting a raw piece of meat in with the lions.”

When questioned about how she thinks the boy will turn out in the long run, LaFave admits to Lauer: “I think he’s going to have a hard time trusting women one day. I’m sure he has to be living with the guilt of quote-unquote ratting me out.”

LaFave is still under house arrest for her crime and, considering her sex-offender status, had to be granted a special waiver to meet Lauer at the posh Westin Harbour Hotel for part of the interview.

LaFave – engaged to hunky high-school sweetheart Andrew Beck – insists to Lauer that she should have the freedom because “I committed a sex offense – but I’m not a sex offender.”

“I made a really, really, really bad choice,” she says.

At one point, Lauer asks LaFave why she thinks her case grabbed international headlines.

“Do you think it’s because you’re pretty?” he says.

“I think so. And sex sells,” LaFave replies.

The interview is set to air tomorrow on “Today” and “Dateline NBC.”