You have not given me reason to trust you considering how Frisk was 'welcomed' to the Underground. [For a moment, once he sinks into the ground, she frowns. And, honesty, is still frowning when he pops back up.]

You know that mischief will not be tolerated, we represent monsters here. [Wait, does Flowey even count as a monster? She's not even sure, there are no monsters like him that she saw before going to the RUINs.]