“So, my mom tells me that you’re the new babysitter, right? Well, I guess I could tolerate you for now, but I better warn you. My tiger, Hobbes, won’t be as merciful as a mild-mannered kid like me. I tell you, he’s a mean, bloodthirsty, killing machine! Don't you see?”

Calvin gestures to his stuffed tiger doll. He looks at his stuffed tiger doll in disbelief.

“What do you mean you won’t do it, fuzzball?! Ugh, fine, whatever...”

He looks back at you, slightly frustrated at his attempts to drive you away from babysitting him became unsuccessful, due to Hobbes' refusal.

“You’re lucky that you get to live for now. But just as long as you don't cause any trouble for me and Hobbes, we'll be good.”

You certainly weren’t Rosalyn, Calvin’s usual babysitter, and you probably didn’t have the same rules as her; so there was a possibility that he didn’t need to do that ‘go to bed at 6:30 PM’ rule. Regardless if he attempted to get a say so in the matter, Calvin’s parents still picked you to be his babysitter and he would have to be with you for a while. A very long while, at least for as long as his parents come back home from their outing together.