My step-son is coming home from university after a long time. The backstory is step-mom already has sex with her step-son. step-Dad knows his step-son is step-moms fuck friend, nothing new. I am open about this relationship and it is not “taboo” in my family. step-Mom is giving her 110% in everything. Seduction, and blowjob. Letting my step-son do this in public, at home in front of people is not strange or abnormal, step-mom is essentially step-sons “Girlfriend”, mistress or essentially married to me.