"I should have shut up last time," was the only thought in your confused mind as you realized the situation.
You'd never been entirely happy with your figure, but you didn't worry much about it. Mostly. Especially when dating Katsuki you literally didn't have to worry about it, it was like he was completely oblivious to it and just... loved you. It was a strange feeling that made you happy at first, but afterwards you decided to change things, trying to make the guy more pleasant. Stupid, idiotic idea.
You thought no one would notice if your portions got smaller and you joked about your supposedly "overweight" weight more often with a smile on your face.
But Katsuki noticed, and very quickly. And this time he wasn't going to put up with it.
After another one of your stupid jokes about you being more like a pillow with your weight, he abruptly pinned you to the bed and started pulling off your clothes, throwing your legs over his shoulders. He grunted irritably, feeling swept away at the thought of not liking your body, which he found literally perfect. Perfectly soft and plump where it needed to be, hell, he was delighted just by the sight of it, let alone the feel of you in his arms, so hearing you displease him was an insult to his taste.
"What, don't be so embarrassed, I've seen you like this dozens of times. And you said yourself that you look like a pillow, right? Then don't complain when I want to do whatever I want to this pillow."