She's deciding which is which based on what Johanna said last time but she would call this fun, now. Not when she came in, but it's become fun at some point. Don't ask her why. (It might be the sweaty body-to-body contact.)

She does sort of a double-take at the kiss, a full-body startle Johanna can feel in the jump of the abs under her face and the brief loosening of the hold around her throat. "What the-- did you just kiss me?" Kate's voice can't quite decide if it's more shocked or laughing. It's leaning toward laughing, even as she's probably struggling to maintain a hold as Johanna takes advantage of her momentary lapse. "What the fuck!?"

There's no conscious decision involved in Kate leaning up and pressing her mouth to Johanna's abdomen, just some gut instinct that she has been one-upped and that can't be allowed to stand. Whatever advantage that gained she'll win back with an open-lipped kiss, necessarily a little rushed and awkward but yes that was tongue at her navel because Kate Bishop does not half-ass things even when they are really weird and stupid and poorly thought-out.