engaging in romantic or sexual behaviors with another person in an ambiguous way that does not necessarily imply monogamy or commitment to a serious relationship. Related to but not necessarily concurrent or synonymous with the terms "talking" and "dating."
She and I have been whatevering all summer, but I doubt anything'll come of it.
Whatevering does not include intimacy - for that I would use other words. Various activities that include mental (for me), <physical>, chat, tele-path-ic stuff.