AH Buffy is engaged to Riley, but best friend Spike(William) steps in for wedding planning

Spike is Buffy's best friend. When Riley proposes to Buffy, but can't help make wedding decisions because he's busy so Spike steps in. Turns out Spike has wealthy family and has to make a decision to take the thrown or money or something. They are at a big house, maybe spike's families house, but Buffy doesn't know he's wealthy but something big goes down at the big house like spike finds out or something idk what. In the end Buffy ends up with Spike

maybe:

For you I will by Slaymuch

This is it. Thank you