"What is the naughtiest thing you have ever done?"

I say after thinking for a little while, looking over at Millie.

Millie nods and says:

"Fair play, I guess that is pretty much the same question I asked you."

Then she looks like she is thinking quite hard for a few seconds, looking into space in front of her, then she turns to me and says:

"I don't really know if there is anything in particular I can pinpoint as the 'naughtiest thing I have ever done', I mean, I have had many interesting sexual experiences over the years..."

Millie pauses for a while, continuing to think, then says, counting on her fingers as she speaks:

"I have had sex with another girl." Millie raises one finger, then raising another finger, saying:

"Three in a bed."

Then, raising a third finger:

"Anal sex." Looking at me, giving me a naughty smile, then looking at her fingers again, raising her fourth finger, saying:

"And I have had sex in public."

Then, holding up her four fingers, she looks at me and says:

"So, not sure which one to specify as the 'naughtiest thing' I have ever done."

Hearing my step-mom talk like this has made my heart beat really fast, and I have positioned my legs so my hard-on is not completely obvious to see. I just sit there and look at her for a while, then realise she is waiting for me to say something, so I say:

"Three in a bed, was that you, another girl and a man, or you and two men?"

"I have done both." Millie replies without blinking.

I feel my cock harden even more, if that is even possible and my heart is pounding in my chest. For a second I hesitate, then I ask:

"Did you get DP'd?"

Millie blushes, then in a quiet voice says:

"Yes."