What did Grendel keep in his pouch?

Well, it sounds a lot like body parts......

"He had this roomy pouch, a strange accoutrement, intricately strung and hung at the ready, a rare patchwork of devilishly fitted dragon-skins. I had done him no wrong, yet the raging demon wanted to cram me and many another into this bag—but it was not to be once I got to my feet in a blind fury."

It was made from "Devil's Skin." I think he tries to stuff Beowulf in it. It is some sort of trophy bag.