AceShowbiz -

Lady GaGa was really comfortable in her own skin. She didn't feel shy to show off her bare chest as she dressed up as a weed when attending a Halloween party this week. "So i was weed for halloween. BEST COSTUME EVER ITS SO FUN," the 26-year-old singer tweeted.

GaGa continued, "Princess High the Cannabis Queen. Photos of party on https://littlemonsters.com/ shortly. and NO 'shortly' is not the new 'SOON.' searches for camera USB in hotel robe with bad hair and hangover. last night was paradise."

The "Born This Way" singer wore a green tutu-skirt with a long green wig. She just covered her nipples with what looked like green stars. Calling herself "Cannabis Queen," she also pretended to smoke pot.

While GaGa was having fun in the party, people noticed that she had lost some weight. It's just a month after she said that she gained some weight. "I was acutely aware of some photos on the internet - my mum called me and was like, 'Did you gain weight?' - everybody was telling me about it, and I didn't really care," she said back then to Stylist magazine.

"I thought, well I don't really care if they think I'm fat, because, quite honestly, I did gain about 30 pounds. I need to be a confident woman and just say politically active things when I can that are helpful to young people," she added.