Known by many Supernatural fans as the fic that broke them, this is a novel-length love story between Dean Winchester and Castiel. It's an alternate universe where Dean and Cas spend the summer of 1965 falling in love — until Dean is drafted in the Vietnam war. Warnings for explicit sexy times, death, and extreme feels. Read it here.

It's THE Marauders fic that defines the major head canons of the fandom. It starts off as letters exchanged by Remus and Sirius in the summer of 1975, and slowly develops their relationship over a year at Hogwarts. With over 200,000 words it's one of the slowest Remus/Sirius builds you will ever read, but SO WORTH IT. Read it here.

It's a love story starring Merlin and Arthur, but set in a modern college setting. Arthur is the Prince of Wales, and Merlin is a student at the University of St Andrews. It's the perfect set-up for feels! Read it here.

This fic is the first installment of a fan-famous series of fan fictions, affectionately dubbed "The Toasterverse." Phil Coulson is fed up with dealing with all of the Avenger's shit, and falls a little bit in love with Hawkeye. There's some bonus Steve/Tony action in there as well. Read it here.

A must-read for every Dramione (Draco/Hermione) fan. And even if you can't possibly see Draco and Hermione getting together, this fic will make you question your beliefs. When Draco and Hermione are trapped in a confined space together, they are forced to slowly begin to understand each other, just a little. Read it here.

The fake relationship trope is a classic for romantic comedies, and this fic does it best. When Louis needs a fake boyfriend to bring to his ex's wedding, Harry is the one to take on the task. It's considered to be a must-read in the 1D fandom. Read it here.

The fic where Germany is a German fighter pilot and North Italy is an Italian resistance member during WWII. And they fall in love. Read it here.

The one where River Song is a Roman empress and the Doctor is her humble servant. In addition to great characterizations, it's a fun to see the power dynamics flipped in this alternate universe. Read it here.

For the perfect characterization of bisexual Steve Rogers, Cap fans turn to this fic. It does a great job incorporating canon from the films into this Steve and Bucky Barnes love story. Read it here.

This short and beautiful fic crafts a lovely narrative of Spock falling in love with his Captain over time. Technically it takes place in the 2009 Star Trek movie universe, but the story could easily apply to the original series as well. Read it here.

We all know the real relationship in this show was Buffy and Faith. This fic imagines what would happen if the two slayers were living together when they were both thirty — totally just platonic roommates, right? (Wrong.) Read it here.

A classic read in the Sherlock fandom, this fic depicts Sherlock and John as actors cast to star as a couple in a new independent drama. Read it here.

This fic takes place in an alternate universe where Derek Hale's family doesn't die, because Stiles saved them all when he was 10 years old. And then he keeps on saving Derek. A sweet and sentimental "anchor" love story. Read it here.

This fic builds on the end of the book series and explores Katniss and Peeta's relationship in the weeks following the war. So if you're stressing about the end of the series with the last movie coming out, have no fear: the story can always go on. Read it here.

This fic fuses with the Inception universe by making Erik Lehnsherr a dream extractor who used to work with CIA agent Charles Xavier. Much drama, angst, and Charles/Erik feels abound. Read it here.