highly inappropriate

Awhile ago The Family went out of town to visit Dad Boss's parents.  The boys each packed a kid roller bag with all the toys they would want for the weekend.  Master kept referring to it as his "fun bag." And because I am super mature, I kept thinking of this:

I may or may not have mumbled that line at some point.  Then, of course, Master heard me mumble something 

MofD:  What did you say?  

Me:  Oh nothing, it was highly inappropriate