Including her opener would assist in thinking up replies to it

"Oh shit, I'll give my harem their marching orders then"

Do the exact same thing and respond back with something in her bio

I think reframing is the best strategy there, b.c. the jokes are just going nowhere good. I'd answer now exactly: "I'm , how are you doing?". Keep some tension avoiding lols/emojis. I'm sure she'll answer it properly and you can go from there.