Ive seen a couple of Mommy, little boy arrangments. One was as Oz metioned however more of a diaper fettish where the submissive spent most of the play time pantomining himself as a helpless child (all 230lbs of him lol). The other arrangamnt I witnessed had the woman in the role of Mother to her son where the boy was being punnished for touching himself with some chastizement while his cock was being held by her and stroked which looked to work rather well considering she was like maby 27 years old tops and the he was well over 50.