How are you going to get out of this? Either way she is going to digest you...unless... "You're bluffing."

"Oh? What makes you think that?" The startled girl asks.

"Well, your tone of voice just now for one thing, but if you were just able to gobble me down here even if I raised a fuss and not suffer some penalty, you would have done so. Instead, you are trying to lure me to some place where I would be helpless. So you can't eat me here if I fight you." You are making your answer up as you go along, but it sounds more and more right as you do.

"Well, aren't you the clever one? Or rather you think yourself so clever. Ignoring the other flaws in your logic, you do realize you have no idea what the rules are here, and you are just guessing at what they say?"

That shakes you a little. "Well, true..., but I think I have guessed right. After all, you still haven't tried to grab and eat me."

"There are a lot of girls who just prefer a girl who does not struggle."

"You didn't say you do, and even if you do, that still means I have some bargaining power." There is a note of triumph in your voice as you say this.

"Alright, you're right. I can't eat you here, but I can hunt you down and eat you later, and if you don't come with me..."

"Oh I will be coming with you."

"Huh?" Hisa's anger turns to puzzlement.

"I have already been eaten by the secretary today, and rather enjoyed it. So I don't mind spending some time in your belly.
"I just don't want to spend the rest of my life there. So you need to give me some assurance I will get out of you alive and healthy. And I am sorry, but you have already tried to fool me, so I need something beyond your word."

"Are you calling me a liar?" An angry Hisa accuses.

"No, no." is your soothing, and lying, response. "I see you will eat me several times in the future, and I want our relationship to start in a situation where we know we can trust each other."

It takes several more mealy-mouthed statements by you to bring her around, but eventually... "I'm not sure why, but I like you, and not just as a snack. Here..." And she dives into her purse. Her hand emerges with a bottle of pills. "Antacids. I take the whole bottle, and there is just no way I can digest you before you ... emerge. That satisfy your fears?"

Well, not completely. For all you really know, these could just be sugar tablets. And she is tricky enough to give you such a false assurance. Still, she could be telling the truth, indeed probably is, and in a school like this, you need some friends. If Hisa will take you under her wing, you are in pretty good shape. So maybe take the risk and go with her to a nice private place where she can gulp you down without being disturbed.

But it is a risk. Maybe you can get her to delay things. Instead of eating you for lunch, she can have you for dinner. Have to give her some payment for the wait of course, but it will give you time to find out if she is telling the truth, or to find some way to be sure you are safe. Of course, Hisa is acting pretty friendly at the moment. You don't want her getting mad at you and ruining what could be a very nice friendship.