Mikey is only after a sh@g. We all watched his audition tape. He doesn't have strong feelings for Grace. He wants a good time, and that's it.
Grace doesn't have strong feelings for Mikey either though. She's no fool. She does like him a lot, but she is certainly not falling for him.
I don't think they did anything under the covers. There wasn't that much movement. As usual, C4 were making something out of nothing so that viewers would talk about it.
And here we are... talking about it...