What would you do if someone asked you a question like this? (NSFW)

I have been friends with this guy for over 25 years. We dated the first six months of those years, but I don’t think of him as an ex, because it’s been so long ago and we were just kids back then. We’re both married and he is a youth pastor (for some reason this fact makes what he asked me even squickier in my mind)

I mentioned on Facebook that I had the night alone without my husband or daughter. He sent a message and asked if I had enough AAA batteries to make the night in bed alone fun. I got totally squicked. Did he really just asked me if I was masturbating? Seriously?

He’s a bit socially awkward, and always has been. But you’d think a minister would know what is and isn’t appropriate to say to someone out of the blue. I am flabbergasted that he’d ask me such a question. I have no idea how to respond.

Am I being to prudish? Do other people make jokes like this and ask people questions like this and I just hang around with the “wrong” crowd? Should I just tell him I think that’s a rude question and leave it at that? Should I tell him off for being pervy or would that be too rude for the question?

I am tempted to just remove him from my friends list with no comment, but after knowing him 25 years, that doesn’t seem right. But I found the question totally inappropriate to the point where even talking about it with him would embarrass me.