>>4398620We technically don't even see them kiss, it's filmed from behind because the main character is spying on them. Really though it's one of the most pointless scenes in the whole series, it's supposed to imply Jodie's character is having an affair then is just dismissed as a platonic friendship... then it's completely forgotten about and never mentioned again. I don't even think the black guy appears again after that.
The series had a very white cast for a BBC programme so I can't help but think the BBC forced the writers to shoehorn something like that in. There's no other explanation for that scene.