John Mayer - John Mayer's Comic Convention Conquests

John Mayer "slept" with nine science-fiction geeks at a comic book convention last weekend.

The 'Gravity' singer joked he seduced several women dressed as Japanese manga heroine Sailor Moon at Comic-Con in San Diego, California.

Writing on his Twitter account, the 31-year-old star said: "This weekend at Comic-Con I slept with nine Sailor Moons. Not an easy task when you're dressed like a Stormtrooper (sic)."

John - who has been single since he split from 'Marley and Me' star Jennifer Aniston earlier this year - also used his profile on the social networking website to make a dirty joke about a fictional race of beings popularised in the 'Star Wars' franchise.

He said: "Sandpeople travel in single file to hide their numbers. This makes them a major letdown in gangbangs (sic)."

It's not the first time the singer has bragged about his sexual conquests on the internet.

In May, he boasted he had persuaded "dozens" of women to leave red lipstick marks on his face during a night out in Los Angeles so the paparazzi would think he had several new girlfriends.

He wrote: "OK, check it. Just spent the last hour getting the reddest lipstick on me for a gag. When you see the pics of me leaving the club covered in kisses it's all a gag."