Masturbation
Masturbation, also known as wanking, was sexual stimulation without a partner, often—though not always—done to pornography. "Wanker" was also an insult.
Fern touched himself while watching pornography that depicted sex between a man and a woman, two women, and two men. (PROSE: A Rose by Any Other Name)
Banksy pleasured himself to a recording of Carys Fletcher and Matt Stevens having sex in his club Nightspot's bathroom: "Go on, son, with you all the way." He was surprised to witness the Sex Gas in Carys turning Matt into a pile of dust on orgasm. Owen Harper later recorded Gwen Cooper's kiss with Carys for later, calling it a "treat". (TV: Day One)
Mrs Linderhof caught her husband "fiddling with himself" on the stairs. (TV: For Tonight We Might Die)
Bernice Summerfield noted that, through his production of literary xenopornography, her husband Jason Kane had "turned himself into a doll for aliens to pleasure themselves with", and had essentially made himself into a product to be consumed by selling pornographic accounts of his encounters "for random strangers to wank over". (PROSE: Sex Secrets of the Robot Replicants)