Gogglebox star Marcus Luther is best known for his witty one-liners on the hit Channel 4 show alongside his girlfriend Mica Ven. But the TV star leads a very busy life away from the sofa as a professional boxing coach who trains his off-screen fighter son.The couple, who are based in south London, are sometimes joined on the show by Mica’s two daughters Sachelle and Shuggy but her two sons don’t appear on their famous sofa.