Personally, I hope that this is a mother and son enjoying some "fun time" before dad gets home from work and that mom is well lubricated for sex with her husband later that night. I also hope that her husband is not aware that their son is lubricating her vagina with family love juice. Her husband might get a upset about the prospect of an additon to the family that was caused by an ince*stuous affair with their son. This unexpected manner of fertilization has happened countless times in families that have indulged in taboo sexual pleasure.