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)

Upon meeting Martha Jones, William Shakespeare was instantly captivated by her beauty and openly flirted with her whenever he could. When the Tenth Doctor promised that they could flirt later, Shakespeare coyly asked if that was a promise, expressing an eagerness to extend his flirtations to the Time Lord. (TV: The Shakespeare Code)