The couple were all smiles as they walked hand-in-hand towards Pandora's flagship Marble Arch store for the #PANDORAwishes campaign.
Ditching the dress, Saturdays singer Rochelle opted for the androgynous look and rocked a tailored black suit with heels.
And didn't she look stunning?! The tux jacket with a sequin collar is actually from Rochelle's own collection at Very.co.uk, and retails at £69. Her tailored tux trousers is priced at £39.
The 25-year-old 'Disco Love' singer kept her hair slicked back and completed her effortlessly stylish look with a slick of bright red lipstick.
On the night, Marvin and Rochelle were joined on stage by Xtra Factor host Sarah-Jane Crawford as they talked to guests and introduced the campaign, which is based around creating an online wish-list in the run up to Christmas.
The couple are just one of many to be involved in the campaign, and last night, their pictures were displayed around the store along with Louise Redknapp and her retired footballer husband Jamie.
And after the night, Marvin and Rochelle still looked inseparable as they were pictured leaving the venue and making their way into a taxi.
Elsewhere, Marvin has teased fans with some exciting news about his dance trio LuvBug.
In the summer, former and he told fans via Twitter last night: "Can't wait for the big @LuvBug news tomorrow. Excited."
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