(also a much shorter fic, much more *obviously* 3SF)

ring the bells that still can ring (1413 words) by AlexSeanchai
Chapters: 1/1
Fandom: Miraculous Ladybug
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Relationships: Adrien Agreste | Chat Noir/Marinette Dupain-Cheng | Ladybug, Alya Césaire & Marinette Dupain-Cheng | Ladybug
Characters: Marinette Dupain-Cheng | Ladybug, Adrien Agreste | Chat Noir, Alya Césaire
Additional Tags: Post-Reveal Adrien Agreste | Chat Noir/Marinette Dupain-Cheng | Ladybug, Nonbinary Adrien Agreste | Chat Noir, Wedding Planning, Romantic Fluff, Identity Reveal, Confused Alya Césaire, Minor Alya Césaire/Nino Lahiffe, Podfic Welcome
Summary:

It was an entirely pragmatic proposal: there are legal and financial benefits to matrimony, and Ladybug and Chat Noir could reduce their separate burdens by harnessing themselves together.