Richards, 68, famous for his hellraising past, including vast amounts of drinking and drug abuse, is much quieter in real life, reported Contactmusic.
"Keith is very quiet. The image he puts over, or people put on him, he's not like that at all. Or not very often. He's introverted and incredibly articulate, even when he was on a lot of junk [heroin]. He's strong.
"My relationship with Keith is very good, but we don't do much more than just laugh at each other," Watts said.
Watts also said how Richards once took in a stray dog during a tour in Russia, which he keeps as his pet to this day.
"The last dog he picked up was on tour in Russia: Rasputin. It was a stray which wandered in backstage and, typical Keith, 'I'll have that.' He fed him some chops and, of course, the dog loved it. From then on it was like living at The Ritz for Rasputin. He lives the high life now in Connecticut with Keith's two pugs."
