Delicate question about sexuality (warning: graphic language)

[Ludovicus]

Hi,
 
As I said in my post of presentation, I am French.
 
Some subjects are quite taboo on french forums and I don’t feel confortable about the idea of talking about the subject of this post with a priest,
 
So, even if I am embarrassed, I thought that this forum would be the best place in order to get answers.
 
Unfortunately, before our conversion, my wife and I committed reprehensible acts, such as oral sex (which, for me, is different from oral stimulation that I considere, based on my researchs and the answers that I got from two traditionalist priests, as being licit) and onanism.
 
By the grace of God I have been able to cease these habits and now it is clear for me that there is only one way to complete a proper marital act.
 
However, I am wondering about the morality of a certain situation.
 
I know that it is licit for a woman that would not have reached orgasm before her husband to stimulate herself (or to be stimulated by him) to completion. It is also licit if, after a first intercourse, the wife and the husband engage immediatley in a second one. In this case foreplay (such as manual or oral stimulations) are certainly allowed too.
 
Is it immoral if, in the two cases that I just mentioned, semen (from the previous intercourse) remains and is « * involved »? The more critical point being probably in the case of oral stimulation.
 
Please forgive the bluntness of my language, I do not intend to shock or disgust anybody. What is shocking or disgusting for some people may be accpetable for others, this is also true for Catholics. I just want to have a clear idea about the morality of that situation.
 
Thank you in advance.
 
Oremus pro invicem.
 
Ludovicus
 
* The word is probably not correct in this sentence but I can’t find an other one.