Father of a Thousand Bastards

A male character with a lot of children out of wedlock, almost always with multiple women. This trope has nothing to do with Mother of a Thousand Young.

Anime and Manga

 * Implied in Sister Princess, where the protagonist has an absent father and a dozen sisters who he'd never met before the start of the story.

Film

 * The concept of Delivery Man takes on this trope as it focus on David Wozniak, who donated his sperm two decades earlier, and now has up to 500 children as a result.

Literature

 * In the Ciaphas Cain book Traitor's Hand, Governor Tarkus' death causes a succession crisis, due to having no heir. However the crisis was made worse due to him preforming "almost two centuries of energetic fornication".

Tabletop Games

 * Forgotten Realms got the King of Cormyr, Azoun IV, who became rather infamous for this. Quoth his Royal Magician (on seeing too many young nobles with familliar features at once) - "Moderation, my liege?" Also, developers on the game side played up his meme-worthy status and Champions of Valor got "Bastard of Azoun" as an optional regional background - right between having music lessons as a kid and birth attended by a celestial creature (of any deity).

Web Comics

 * Julio Scoundrél from Order of the Stick is heavily implied, if not out right stated to be this.

Western Animation

 * In Family Guy, due to the promiscuity of Glenn Quagmire, it is often joked about that he probably has many children he doesn't know about. One episode even has him run into a bunch of what appear to be his children all in different classrooms in the same school.