Spoiler (click to show/hide):
https://cs.sankakucomplex.com/data/33/67/3367016e096e72f8cebddc89bfee2e22.png?4586009 this, except in a tux and obviously not baking lol
Before you headed downstairs, Starlight wished you a nice evening, and you heard Sweetie Belle giggle a bit to the older mare as she admitted "Kinda hope Rarity doesn't go for him... he cleans up really nice and he's always been so nice to me." This makes you feel... just a bit strange. You were giving Spike an open and honest chance, and Sweetie was already hoping you'd reject him?
That must have meant she didn't expect you to really give him a shoot... you were just doing this to be nice, to be generous. Well, you could show her, and anyone else who was thinking that. Starlight was behind you either way after all!
Heading on down, you do indeed see Spike sitting on a seat, his small B-cup breasts not quite as obvious in the Tux he was wearing. He perked up, cheeks flushing bright red when he saw you. "W~Wow... w~woah Rarity... y~you look even better then you already do. D~Didn't think that was possible with how beautiful you are."
He takes your arm, smiling a bit as he says "I~I hope you don't mind a bit of a ride where we're eating. T~They should be arriving in a moment."