She shared a series poster for Usman's new web series Yahoo Boy with a sweet message. "Yahoo Boy series coming soon! So excited for this," she began. "No matter what, we will always support each other! That's what grown ups do! So proud of Usman for this!"
The Nigerian singer showed his appreciation for Kim's praise in his own Instagram Story post. "Queen in America and Queen in Africa," Usman wrote. "Queen Kimberlllllly thank you friend."
During season 7, Kim visited Usman in Nigeria and tried to win the blessing of his mother. However, family tension grew as Usman was required to take a younger wife — something Kim would only agree to if she could marry Usman first.
By the end of the series, Usman's family had agreed to let the couple wed, and two romantic proposals by Kim and Usman followed. However, Usman's wish to adopt his nephew triggered the end of their relationship.
The exes remained on good terms during the tell-all, and clarified they haven't romantically reunited since viewers saw their blowout argument at the end of season 7. However, they still talk "every single day," Kim said, calling Usman her "best friend."
Kim also admitted she's open to a physical relationship with Usman in the future. "We're friends, but we're cool ... I told him, we can just be friends with benefits, I'm good with that. I told him that," she said during the tell-all.
The reunion episodes proved not everyone thinks as highly of Usman as Kim does. Kim's own son, Jamal, slammed the Nigerian musician for the treatment of his mother.
"I think his intentions with my mom were selfish and narcissistic," he said during the tell-all. "You put her in a position where, obviously, you knew she was already head over heels for you before you were in a relationship, calling her potential and all that bulls—. You knew you had her. You worked her and broke her down."
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An all-new season of 90 Day Fiancé: The Other Way premieres Sunday at 8 p.m. ET on TLC.