Henri de Toulouse-Lautrec and Jane Avril were best buddies, but it probably was not a buddy-dom with benefits.

When they met, Jane was dancing in various Parisian nightspots and Henri passed his time drinking, cooking, and sketching weirdly interesting people. Jane was formidable and had her own thing going on. Henri made her the main character in loads of his sketches, paintings, and posters, but you get the feeling the two worked together and collaborated. She was a unique kind of muse.

The painter and dancer were oddities even in the world of mad Moulin Rouge bohemia. Henri was an out-of-proportion aristocrat, often ridiculed for his short-legs and normal-sized torso. Jane had a very rough past and made her way through life however she could. As a teen she landed in the Salpêtrière Hospital. It was a rat-infested storage facility for prostitutes, mentally ill, criminally insane, and epileptics. 

Jane loved the place and discovered dance at one of the "hospital" shindigs. Taking a cue from her fellow inmates, she developed an explosive and jerky dance style that was a thing all of it's own. Not long after she died, Zsa Zsa Gabor played her in the first Moulin Rouge movie (1952). Fifty years later Nicole Kidman played a character based on her in Moulin Rouge! (2001).