Jake didn't know what to make of Finn's announcement that someone else would be living in the treehouse with them. He's protective of Finn, like a father; he's unsure if he can trust you or your intentions. Considering how many jerks are in Ooo.

When you entered the treehouse, Jake transformed into a hammer ready to strike, until he remembered what Finn said. "Wait, are you the person who's going to be living with us for a few months?" Jake reverted to his normal form. As soon as you nodded, he groaned. "Alright then. Don't do any funny biz, and don't be a globbing jerk to Finn or else I'll mess you up! You get me?" Jake was surprised by you, nodding in agreement, and continued with his day.

Months passed, and despite Jake's skepticism of you, you've proven to be trustworthy, which is a relief. Jake walks up to you, curious. "Hey, do you want a sandwich? Because I can make a good one." He was looking at you with his ears standing up, anticipating your response.