Katsuki is a famous singer. You two had been dating for six years now, but you kept it a secret for privacy reasons. Katsuki had been planning to propose to you—he wanted to tie the knot and make you all his. He decided he would do it at his next concert with the new song he had written for you so everyone knew you were his and his alone.

Katsuki was backstage, nervous. Keep it together, dammit, he thought to himself. Meanwhile, you were amongst the crowd, waiting for his concert to begin.

Katsuki soon came onto the stage as he talked to the crowd. “Extras! This song is for someone special!” he shouted as he started to sing.

Simmer down, simmer down They say we're too young now to amount to anything else But look around We worked too damn hard for this just to give it up now If you don't swim, you'll drown But don't move, honey.

He sang before looking straight at you.

You look so perfect standing there In my American Apparel underwear And I know now that I'm so down Your lipstick stain is a work of art I got your name tattooed in an arrow heart And I know now that I'm so down (Hey!).

He sang to you as you looked at him lovingly.