The first post saw the pair dressed as 90s cultural icons Pamala Anderson and Tommy Lee.
Earlier this year, a successful Disney+ series about the two former lovers dropped and received critical praise.
Watch Megan Fox open up about her ‘deep insecurities’ in the clip below…
Their second Halloween outfit sees Kelly, whose real name is Colson Baker, wear robes that a Catholic priest would wear, while Fox wore black latex lingerie and high boots.
The couple can both be seen clutching rosary beads while a video shows the rapper feeding his fiancée communion while she is on her knees.
“On Sundays, we take communion,” Fox captioned the snaps.
The post has not gone down well in the comments section, with many people slamming the couple.
One person said: “What happened to cultural appropriation? Why is it wrong to dress up as an Indian but okay to mock the Catholic faith?
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“It’s absolutely abhorrent and offensive and I’m so sick of the double standard!”
“Unacceptable. No one should ever mock someone else’s religion,” a second user added.
Another person slammed the couple, by adding: “I’m not Catholic but this is so WRONG AND IN SO MANY WAYS making fun of religion. Respect requires respect so you guys lost mine. Respect the Bible!!!!”
“This is just distasteful and I’m an atheist,” added a fourth person.
Someone else said: “Woman I do really love you but please leave religions out of the costumes.”
However, the couple’s first outfit also caught attention for the wrong reasons.
Some people took to social media and said the pair were glorifying Anderson and Lee’s relationship by dressing up as the ex-couple.
One said: “How incredibly distasteful of you.”
Another added: “This is dumb and insensitive.”
“Megan, this is not the serve you think it is,” a third follower remarked.
At the time of writing, Fox and Kelly have yet to respond to the backlash.
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It’s not the first time Fox and Kelly have raised eyebrows when it comes to their relationship.
Earlier this year, the couple confessed to ‘drinking each other’s blood’ when celebrating their engagement.
In an Instagram post on January 12, the Jennifer’s Body star penned: “In July of 2020 we sat under this banyan tree.
“We asked for magic.
“We were oblivious to the pain we would face together in such a short, frenetic period of time.
“Unaware of the work and sacrifices the relationship would require from us but intoxicated off of the love. And the karma.
“Somehow a year and a half later, having walked through hell together, and having laughed more than I ever imagined possible, he asked me to marry him.
“And just as in every lifetime before this one, and as in every lifetime that will follow it, I said yes.
“…and then we drank each other’s blood.”
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