There is a phenomenon known by the ponies close to Twilight as Twilight Sparkles Romantic Radius. The nature of this phenomenon is that any pony (un)lucky enough to successfully woo the Princess of Friendship is going to end up with at least two extra suitors besides the Princess herself. So it was that Tempest Shadow found herself married to Pinkie Pie and dating Rarity, the latter of whom she was currently working with on a new garment for some dinner or another.

Oh! I almost forgot. Tempest has a dick in this one cuz she's trans.