The girl has gotten very into milking the boy. Making him come while still locked in chastity. she usually does this by fisting him hard until he goes into convulsions.
THe boy is kept locked up for a week or more at a time. During that time the girl likes to keep him very aroused by tormenting and teasing him. THis week though, the boy took one of the strapon harnesses and put a dildoe in it to use on the girl. He woke her up by fucking her. The girl was very confused at first, how could he be fucking her when he was locked up?
So now we have a new activity in our bag of kinks, his and hers strapons. and we take turns, both of us strapping on and fucking each other.