Well, it's good to have a familiar at your service, but it's something alse to have a familiar that is bigger than you and doesn't listen! Yuuki is trying to get to it's face in order to solve this, but...i guess Sorrel figured out that looking smug immunize him from any punishment from Yuuki? In all cases he's clearly not worried!

Well, there's a more logical explanation about what Yuuki is trying to do, but it's spoiler territory. Maybe one day this picture will make senses!

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Sorrel and Yuuki belong to  Muhny