He was bored. Bored was usually dangerous with the cub, since he was a bit unpredictable. He did was he wanted, and only what ended up well for him in the end. There were few he would do otherwise for. His family, however, ranked high in his mind. He cared for them.
So when he heard the loud roar like sound, he responded at once. He knew the call, it was one of his sisters. It didn't take long for him to get to her, he had been rather close. So when he saw Sif rolling around on the ground, he cocked his head and looked at her curiously. Clearing his throat, he arched an eyebrow.
"What exactly is it you're doing, sister?" He asked. He knew his family was a bit weird sometimes, but this was taking the cake for the moment. She was rolling around like a warthog.