The actress reprised her role as substitute teacher Holly Holiday, and had to dance the Argentine tango with Morrison, who plays teacher Will Schuester.
He told website Access Hollywood, 'We're doing the Argentine tango, so you're in-between their legs and you're kicking up and stuff.
'So she's kicking in here [inner thigh], and she's like, 'I'm so scared that I'm going to hit your man-love!'
'And I said, 'You know, just go for it.' And she did and she connected a couple of times.'
He added that his love life is certainly hotter on-screen than off. 'I'm not dating anyone. I don't feel like I'm in a good place to be a good boyfriend,' he said.
'I know how much work it is to be in a relationship and I don't have the time to put in that work right now.'