Marroquin confirmed his romance with Briana DeJesus, who joined the MTV series in Season 8, in an interview with People published Tuesday.
"We are dating," he told the magazine. "We've been friends for a while and we weren't in a rush."
Marroquin said he and DeJesus "decided to make it official" after seeing each other at a reunion taping over the weekend. The pair had hinted at their relationship by posting photos together on Instagram.
"Daddy Javi," DeJesus captioned a picture with Marroquin on Friday.
"I have a 6 pack from laughing so hard these last couple of days #IMY #SCORPION #BAE," Marroquin wrote alongside his own photo Monday.
Lowry, who split from Marroquin in May 2016 after nearly three years of marriage, posted a cryptic tweet Wednesday after news of her ex-husband's romance broke.
"Lmao don't [expletive] where you eat," the 25-year-old reality star wrote.
Lowry shares 3-year-old son Lincoln with Marroquin, 7-year-old son Isaac with ex-boyfriend Jo Rivera and 2-month-old son Lux with ex-partner Chris Lopez.
She denied in September that she cheated on Marroquin during their marriage.
"There's, like, a whole misconception that I cheated on Javi while he was deployed, which is super frustrating because that's not the case," the star told E! News. "It's not true."
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