A challenge, a tease and a gesture of trust -
Surprise me is all three. A Bearer may be testing your mettle, Receiver, wishing to understand you better, or simply be seeking excitement or interesting experiences with a valued companion. The precise nature of such experiences, of course, is limited only by the Receiver’s imagination. Responses can vary from the confident
See you soon to the disbelieving
You've gotta be kidding me. Of course,
Surprise me can also be sent as an ironic response to some declaration of the Receiver’s - perhaps
Someone else?, or
It's complicated? - as well as deflating somewhat the self-conscious
Evil laugh.