After his initial rush of gratitude, he couldn't help but wonder if maybe it was just a coincidence.
There was certainly no reason his most hated enemy would leave him that ear of corn, after all. And to be frank, he was feeling a little vulnerable after being banished by Ludo, so doubt was quick to creep into his mind. Maybe she had just set it on the windowsill and forgot about it (except why would she leave a plate of food there like that)? Or maybe she had poisoned it (though honestly, that wasn't really the Princess's style).
Then the next morning, he found a plate of eggs and toast sitting on the same windowsill before Star and her little karate boyfriend left for school. The eggs were a little overcooked and had some shell stuck in them and the toast had been slightly burned, but it was all edible and it was clear they were left there intentionally. He wondered then if it was a ploy to get information out of him about Ludo, and a feeling of discontent welled inside him. Whatever betrayal he had suffered at his Master's hand, he would not betray him so easily for a few measly morsels.
(Though Toffee was probably fair game, right?)
To his surprise though, the Princess never once tried to coax him into betraying Ludo's secrets. She never spoke to him at all actually, and he never quite caught her leaving him food day after day after day. It seemed he'd just turn around and find it there with her small form darting away from the window.
It was almost frustrating how confusing the girl was. Why couldn't she just behave like the enemy she was supposed to be, so he could eventually catch her off guard and steal the wand to redeem himself to his Master?
Then one day, a bad storm hit, which threatened to knock Buff Frog out of his tree.
He was considering the risk of breaking into the Diaz' storage shed for shelter against the rain and lighting, when suddenly a pink dome of magical energy materialized, protecting him from the elements. Turning, he found himself face to face with the Princess of Mewni, half hanging out the window with her wand in the air so she could cast her spell.
For a moment there was only silence as the two stared at each other, uncertainty and hesitation on both of their faces. Then, the princess seemed to come to a decision and determination flashed in her eyes before she squared her shoulders and met Buff Frog's gaze with her own.
"There's room inside." She stated, her voice quiet, but firm as it carried over the sounds of the storm. For a moment, Buff Frog felt conflicted, certain that this was all some sort of trap. But as he mulled over his options, lightning struck nearby, startling the monster into letting go of his branch.
Moments later, Buff Frog found himself standing awkwardly in the Diaz's family foyer, dripping water all over their very nice rugs.
Star was silent as she led him up the stairs to her room, stopping over in the bathroom long enough to grab some towels which she offered him wordlessly before letting him into her chambers. All around, creatures of various shapes and sizes slept peacefully despite the raging storm outside, and with a quick flash of light, there was suddenly a new bed available for him.
Curious, Buff Frog turned to look at the princess, certain there had to be some kind of catch for all of this. But Star didn't even look him in the eye as she climbed into her own bed, sitting against the headboard with a pillow hugged to her chest.
Hesitantly, Buff Frog climbed into the bed Star had conjured for him, marveling in the warmth and comfort it provided.
"Do you hate me?" Buff Frog jumped a little at the unexpected question from the uncharacteristically quiet princess, turning back to her with a look of confusion. She kept her eyes glued to the wall though, her feathered shield held so tight against her that it seemed in danger of bursting.
The monster considered the Princess' question for a moment. He knew, logically, the answer should be yes. A few weeks of pity meals didn't make up for a lifetime as enemies, after all. He didn't have to think hard to recall all their most humiliating battles, and how Star managed to make him look like a fool so many times.
And yet… despite that…
"No." Buff Frog answered gruffly, to the surprise of both the princess and himself. Before Buff Frog could consider his own answer for too long though, Star flashed him the most grateful, glowing smile he had ever in his life received, striking the monster dumb for a moment.
"Thank you." Star said, before replacing her pillow to its proper place and turning away from him to go to sleep. For a minute, Buff Frog didn't know how to process any of that. What was SHE thanking HIM for? For that matter, why was his opinion of her so important in the first place? Buff Frog was tempted to ask Star to elaborate, when suddenly the wand glinted in the moonlight and the monster went still.
It was right there. He could just take it, the second Star fell asleep, then steal her Dimensional Scissors and sneak back to Ludo. Prove his loyalty and competence once and for all, and rub it in that jerk Toffee's face. It was right there, practically within his grasp.
But somehow, one look at the sleeping princess was enough to make the dark enticement of the wand disappear.
Rolling over on his side, Buff Frog closed his eyes, surrounded by the soft breathing of Star and her many pets mingled with the sounds of the storm outside, which now seemed light years away. He didn't understand yet what this arrangement was about, or what Star hoped to gain from helping him but, oddly enough, he felt more at peace there in the bedroom of his enemy then he had felt for quite some time now.
…At least until he woke up the next morning to a surprise attack from a half panicked Marco Diaz.