Of course it is. Warning: This article contains content some readers might find objectionable.
"Life-sized boob mouse pads" (等身大おっぱいマウスパッド or "toushindai oppai mausu paddo") have been released in Japan for well-over a decade. Some people think they're harmless fun, while others don't like them. In the past few years, however, the these mouse pads have gotten truly life-sized.
To put this into context, this Honoka mouse pad weighs around 2100 grams, 1600 of which is the character's chest and which sounds like serious back problems.
According to major Japanese news site Biglobe, the mouse pads feature Honoka and Marie Rose. They are made in Japan by skilled artisans, apparently, using a special super soft material. The company that creates them, Softgarage, tells Biglobe that these are the "biggest and softest mouse pads on Earth".
In case you missed it, check out Kotaku's review of Dead or Alive Xtreme 3 here.
[h/t to Sang!]