play footsie
Behave coyly, flirt with, especially secretly. For example, Get to the point, there's no need to play footsie with us. This expression alludes to two persons surreptitiously rubbing each other's feet together. [1940s]
Cooperate or curry favor with in a sly or secret way, as in The mayor's been playing footsie with various neighborhood councils. [Mid-1900s]