Shion is basically me with cats.

Not the miko!

People who can be conceived as clever won't dare to touch a cat's belly... with their hands.

If you dare to use your face, there you have the consequences.

Deathwish granted

Rin knows not to do this to reimu on account of her miko hax powers but shion? She's open season.

In my experience, cats have a limited patience for these sort of things. The one who initially riled them up won't be the target of their wrath.

Using your face is fine. What's the cat gonna do, biting my hair?