Lady Gaga stripped down to her bare essentials for none other than Tony Bennett, whose charcoal sketch of Gaga is now up for auction on eBay, with all proceeds going to charity.

The original portrait of a nude Lady Gaga stretched out and propped up on her elbows was drawn with charcoal measuring 18 inches by 24 inches.

Bennett signed the work "Benedetto," as he does with all of his paintings and drawings. Reports are that the portrait grabbed £3200 and the money raised will benefit Gaga's Born This Way Foundation and Bennett's Exploring the Arts Foundation.

(From E News)