The former couple are both serving prison terms for killing Gypsy Rose Blanchard's mother, Dee Dee Blanchard

The former boyfriend of Gypsy Rose Blanchard, the woman who orchestrated her mother’s murder after years of abuse, fondly recalled the couple’s time together in the days prior to the headline-grabbing killing, referring to Gypsy as his “soulmate” in a new interview.

Nicholas Godejohn, 30, is currently serving life in prison without parole for his role in the June 2015 stabbing of Dee Dee Blanchard, who had forced her daughter for years to portray herself as terminally ill.

But in a preview for the upcoming Oxygen special Gypsy Rose & Nick: A Love to Kill, Godejohn has nothing but fond memories of the days he spent with Gypsy surrounding the killing.

“That was, man, probably the best days of my life, that’s the only way I can describe it,” he said in an interview from prison. “I enjoyed every second of it.”

The convicted killer continued, “From the very beginning, I just knew we were soulmates. Those five days when I was actually with her, physically with her, those five days were the most intense, and magical, and awe-inspiring days I’ve ever had.”

Godejohn, who met Gypsy online and traveled from Wisconsin to her home in Missouri to see her, said he had already started planning their future together as a couple.

“I was gonna get a job and start looking for an apartment. After a little ways down the road, I’d probably end up marrying her and end up having children with her,” he said. “That’s something I’ve never had with someone else. To this day, she’s the only one I’ve ever had that with.”

The preview also included home video clips shot by Gypsy, now 27, that feature Godejohn laughing as he eats a brownie.

Gypsy and Dee Dee BlanchardCredit: GREENE COUNTY SHERIFF'S OFFICE
Gypsy, at left, and Dee Dee Blanchard
| Credit: GREENE COUNTY SHERIFF'S OFFICE; Inset: Uncredited/AP/REX/Shutterstock

Police allege that Gypsy enlisted Godejohn’s help in plotting her mother’s murder, and he told 20/20 last year that she masterminded the killing after Dee Dee ordered her to stay away from him.

Godejohn said in the new interview that he felt killing Dee Dee was imperative to ensuring he and Gypsy could spend their lives together.

“Somehow I just knew, deep within my heart, some way me and her would end up being together in the end. There’s no other option, we gotta do it,” he said, referring to the murder. “I wanted to make sure her mom was not going to harm her anymore. I made sure of that.”

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Credit: Courtesy HBO

Experts have said that Gypsy was the victim of Munchausen by proxy, a rare form of abuse in which a guardian — in this case her mother — exaggerates or induces illness in a child for attention and sympathy.

Dee Dee had told their community that Gypsy was a terminally ill teen with the mind of a 7-year-old who suffered from muscular dystrophy, leukemia and other ailments.

Gypsy is currently serving a 10-year prison sentence after pleading guilty to second-degree murder.

She has since moved on from her romance with Godejohn, and a family friend told PEOPLE in April that she was engaged to a man she met as a pen pal while in jail.

The family friend added that she believed Gypsy’s relationship with Godejohn was unhealthy and an act of “desperation.”

Gypsy Rose & Nick: A Love to Kill airs Saturday on Oxygen at 7 p.m. ET.