The engaged couple – who met on X Factor last year – entered the CBB compound this evening and, like Heidi and Spencer did in a past series, they will compete as a couple.
But Stevi knows it is a risk.
"It could make or break us. That is the thing. It is a chance and some risks are worth taking. It could make or break, who knows," he said.
Fellow singer Chloe added: "It is very common for people to come out of reality TV shows and immediately be branded with the showmance stamp. That really upsets us because of the time we have invested in each other and we really do love each other so much.
"So although it is not our main aim, we still want people to see that we can function as a normal couple despite it being such a surreal situation - it's a game show! Obviously there are intimacy issues and things that we'd rather not share on camera. We are going to try to be as normal as possible."
She added: "I was really surprised when Stevi wanted to go in as a couple. He is literally the most important person in my life and love and adore him and it is a massive time in a relationship to go on TV. You have to be really sure in who you are as people and in the relationship. So for both of us to make that commitment is a big decision. We are really excited but really scared."
CBB airs nightly on Channel 5
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