MIC viewers last night watched as Stevie kissed Stephanie during a sightseeing tour of London, having previously taken Riley on several dates.
Stevie had also reassured Riley that he isn't like serial cheat Alex Mytton and, when he is in a relationship, he remains faithful to his girlfriend. Taking about their "situation", he blew her a kiss and said: "I love hanging out with you, I think you're great."
However, later in the show Stevie took Stephanie on a trip around London - before kissing her on a rooftop while overlooking the London Eye.
While at Jamie Laing's picnic, Louise Thompson's brother Sam decided to tell Riley what had happened. Looking upset, Riley said: "I wasn't expecting that. I kind of feel like a bit of an idiot. I've gone around [saying] 'He's such a nice guy, he's so different to everyone else'.
"This kind of proves he's not. He's doing what everyone else is doing. I just really didn't see that coming." Stevie then said to Riley that he was going to tell her, had Sam not got there first.
Last night, following the episode, Stevie took to Twitter and admitted: "Could have handled the Riley situation better. But I was single, and went after what I wanted. Wouldn't you? #madeinchelsea."
He also retweeted a fan, who had posted: "@StevieJ_23 also Riley needs to clock that you were going to tell her right then and it wasn't your fault Sam got there first."
Riley, meanwhile, has stayed silent while Stephanie has pointed out that Stevie wasn't "married" when they kissed.
I have a feeling Riley is doing great! They went on 1 date guys, y'all watched it last week... A casual date is not a marriage. #fairgame— Stephanie Pratt (@stephaniepratt) May 26, 2014
Now back in Los Angeles, US star Stephanie tweeted: "I have a feeling Riley is doing great! They went on 1 date guys, y'all watched it last week... A casual date is not a marriage. #fairgame."
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