I was invited to a couple's house to be blowed in an homemade gloryhole. I have never done this so I have several questions. I am a bit afraid of STIs, what's the risk for me, they told me she is tested clean regularly. Is a condom a dealbreaker? It's also being a long time since I was sucked, and I have never been deepthroated (which is the main "theme" of this event). So I am worried about cumming fast. Is it accepted to ask for a second round? This couple is anonymous, I just know they are friends of a friend. I don't know if the man is straight or bi. How could I know who's blowing? Could I ask to touch the people on the other side (maybe sexually)?

Sorry for the long text but I am a beginner and sorry if it's the wrong place