On Tuesday, the rumored couple stepped out with some friends, first heading to watch Top Secret Comedy before making their way to Project Club in London.
But their night didn't end there. After leaving the club just before 2 a.m., the group went to a house party in Fulham, a neighborhood in London, where they partied until almost 3 a.m.
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The One Direction singer and The Originals actress hit the streets in style with Campbell, 20, wearing a high-waist leather skirt with a white cropped shirt, staying warm with a gray trench coast and black booties. Tomlinson, 24, kept in simple in all black, donning an Adidas sweater.