Flirting

The Ninth Doctor claimed that, for Jack Harkness, merely saying hello was flirting. (TV: Bad Wolf)

Clara Oswald enjoyed flirting with the Doctor. (TV: The Bells of Saint John - Hell Bent) Her Oswin Oswald echo flirted with Rory Williams to help take both their minds off the horrors of the Dalek Asylum. (TV: Asylum of the Daleks)

The Master's and  incarnations flirted with one another. (TV: The Doctor Falls)