So you're saying that you want me to write new dialog trees for when you come back for a second helping?
I think that if a player comes back, they shouldn't have to play the same pre-game again, and just fast-forward to the foreplay (in this case the handjob) with new dialog. Something simple, like:
"Back again so soon? I'm ready for more if you are..."
Honestly I'd consider using that, or some variation thereof, for all the times a player comes back for seconds.