Question: What was the king whose mistress was Elżbieta Branicka criticized of as the last king of the Commonwealth?

Context paragraphs:
Martin Knight (author): Martin Knight is a British author born in Epsom in Surrey in 1957 mainly associated with working class culture and football literature.  In 1999 "Hoolifan" and "The Naughty Nineties" were released; both books dealing with the subject, culture and history of football hooliganism.  Knight was co-author with Martin King whose hooligan memoirs form the core of the books.  Irvine Welsh provided the introduction to the latter book.  As partners, Knight and King produced "On the Cobbles" the story of Jimmy Stockin a renowned gypsy prize fighter, "Ossie – King of The Bridge" – the autobiography of Chelsea footballing legend Peter Osgood and "Grass" covering the exploits of major drug smuggler and Howard Marks' cohort Phil Sparrowhawk.  In September 2010 a copy of "Ossie – King of the Bridge" (among other items) was buried beneath the new statue of Peter Osgood unveiled at Stamford Bridge.

Alara of Nubia: Alara was a King of Kush who is generally regarded as the founder of the Napatan royal dynasty by his 25th Dynasty Nubian successors and was the first recorded prince of Nubia.  He unified all of Upper Nubia from Meroë to the Third Cataract and is possibly attested at the Temple of Amun at Kawa.  Alara also established Napata as the religious capital of Nubia.  Alara himself was not a 25th dynasty Nubian king since he never controlled any region of Egypt during his reign compared to his two immediate successors: Kashta and Piye respectively.  Nubian literature credits him with a substantial reign since future Nubian kings requested that they might enjoy a reign as long as Alara's.  His memory was also central to the myth of the origins of the Kushite kingdom which was embellished with new elements over time.  Alara was a deeply revered figure in Nubian culture and the first Nubian king whose name has come down to scholars.

Adikhalamani: Adikhalamani was a Kushite King of Meroe dating to the 2nd century BCE.  Adikhalamani was the successor of King Arqamani and was later succeeded by a king whose name has only partially survived: (...)mr(...)t.  He is said to be contemporary with an Egyptian revolt dated to ca. 207-186 BCE.  During this revolt a ruler, Horwennefer (who may have been a Nubian) took control of Thebes and revolted against Ptolemy IV Philopator.  The revolt ended ca. 186 BCE when Ankhwennefer (his successor or more likely Horwennefer with a different nomen) was captured and executed.

Blood Mania: Blood Mania is a 1970 American horror film written by Peter Carpenter and Tony Crechales and directed by Robert Vincent O'Neil, and starring Carpenter, Maria De Aragon, Vicki Peters, Reagan Wilson, and Alex Rocco.  The film stars Carpenter as a doctor whose mistress, an heiress, murders her terminally ill father to help him pay off a debt.

Palacus: Palacus or Palakus was the king of Lesser Scythia who succeeded his father, Skilurus.  Resuming the latter's war against Mithridates the Great, he attempted to besiege Chersonesos but was defeated by Pontic forces under Diophantus.  Enlisting the assistance of the Rhoxolani under Tasius, Palacus launched an invasion of the Crimea.  The invaders were defeated by Diophantes and accepted Mithridates as their overlord.  Palacus was the last Scythian king whose name is attested in classical sources.

Stanisław August Poniatowski: Stanisław II Augustus (also Stanisław August Poniatowski; born Stanisław Antoni Poniatowski; 17 January 1732 – 12 February 1798) was the last King of Poland, Grand Duke of Lithuania and the last monarch of the united Polish–Lithuanian Commonwealth (1764–95).  He remains a controversial figure in Polish history.  Recognized as a great patron of the arts and sciences and an initiator and firm supporter of progressive reforms, he is also remembered as the last king of the Commonwealth whose election was marred by Russian involvement.  He is criticized primarily for his failure to stand against the partitions, and thus to prevent the destruction of Poland.

The Money Habit: The Money Habit is a 1924 British silent crime film directed by Walter Niebuhr and starring Clive Brook, Annette Benson and Nina Vanna.  It was based on a novel by Paul M. Potter.  The screenplay concerns a man whose mistress helps him con a financier into buying a worthless oil well.

Elżbieta Branicka: Elżbieta Branicka (c.1734-1800) was a Polish noble lady, political plotter, mistress of King Stanisław August Poniatowski.

Elżbieta Szydłowska: Elżbieta Szydłowska, married surname "Grabowska", (b. 1748 – d. 1 June 1810) was a member of the Polish gentry, a mistress and possibly the morganatic wife of the last King of Poland, Stanisław August Poniatowski.

Fastida: Fastida was a king of the Gepidae of the 3rd century.  His battle against the Visigoths resulted in defeat, and was chronicled in Getica by Jordanes.  He is the first Gepidic king whose name survives.

Supporting paragraphs: Elżbieta Branicka Stanisław August Poniatowski
Answer: failure to stand against the partitions, and thus to prevent the destruction of Poland