There is probably non denying the fact that the kiss was out of affection. House had seen in Cuddy a "comerade" in his world of suffering. Remember what the rape victim, who did not want to talk to anyone other than House, asked him: ARE YOU HAPPY? The question was a deeper exploration into the life of the show's main character and it is one that he answered quite frankly and without any flowers attached to the answer. You could see and feel him hurt in the way he answered, because that question really did cut through his facade of sarcasm; I think he saw that in Cuddy's eyes and because he is the only one that can appreciate the destructive nature of such a level of sorrow and pain, he felt sorry for Cuddy. But is someone as damaged as House is, capable of pitying others?
I, at least I, am that one there is, who doubts the preamble that the kiss was out of affection. Let's not get jazzed about a Cuddy-House relationship. It's not gonna happen. It'd be dull for the show and to be honest, House is not interested in any other woman, other than the one he lost. Of course, House'll act next morning as if the Earth had not just finished a round around the Sun and make believe that nothing happened. It will be so effortlessly deliberate that Cuddy, in spite of how well she's used to that sarcastic nature, will still be baffled. Did you guys see the expression on Cuddy's face after the ordeal? It was not just a surprise, but a fear that momentarily made her sorrow vanish. Cuddy as we know her is going to ask for a date or something, maybe House will oblige, but tell her at the date something I've been saying for sometime and and something House himself has confirmed: Cuddy is a great asset to House and everything that concerns Cuddy, concerns House, in that he has to find ways to avoid a replacement of his boss, which would represent change - one thing he abores - and it would take some time before he figures out how to manipulate some new "fool" without getting them to fire him, because no one other that Cuddy woud employ House. I think, therefore, that House:
1. kissed Cuddy to console her and prevent her from becoming self-destructive or falling into some deep depression, because apparently that's what was coming.
2. didn't like the idea of a baby, because that would mean time off the job to be spent with the baby, which in turn would mean a new face in Cuddy's office.