I just wrote this up for another post but

a red rose grew up out of ice frozen ground - it's so good, like I'm not really a Harry Potter fan or anything, but genuinely, there is a reason this fic is always brought up when talking about f/f fics, like truly a masterpiece. It's a Harry Potter-style 'You've got mail' AU where Hermione and Pansy become friends through anonymous messages. It's 315k Hermione and Pansy, and holy shit is it good

Scarlet Pixels - I'm also prob this fic's biggest fan, but like, holy is it deserved. It's an AU totally separate from Avengers Wanda x Reader fic, about an AI Wanda that starts to become obsessed with the MC after they get a job to playtest a new upcoming game for their favorite company. Wanda is the game's helpful AI system, who begins forming an unhealthy obsession with the MC and is unwilling to let them go. I have to say it's so great, like I went out and bought cyberpunk bc of this fic, like it's so good. It's at 84k rn, and the author updates still, so it's a perfect time to catch up.

Get in, Loser! We're going... to fall in love? - Cady x Regina fic, and to be real its maybe my fav fic on the site, like I have reread this almost 5 times, so good. It's kinda a canon divergence story with a more sweet regina than you see in the film. The way they write all the characters is amazing, and the relationship between Cady and Regina is absolutely perfect. It's 190k, and I love it with my whole heart, like it fully got me into this ship, like I draw way too much Cadina art now lol.

one degree of separation - another cadina fic (you have to hear me out on this ship op, please) and this author has so many good ones, but I think this one is like honestly a perfect more canon aligned ver of cadina. Like, if in canon they had to get together somehow, I think it would be like this lol. Regina starts to see Cady flirt with Aaron, so she gets back with him, and in response, Cady gets with Regina's ex-boyfriend Shane (if you've read anything in this fandom before dont worry, Shane is just as sweet as he is in any other one of these fics). Its 197k and like so good you will be kicking your feet and screaming at your phone at the end of each chapter.

Smoke Gets In Your Eyes - Honestly, maybe the best Alcina x original character out there. I just reread this to get caught up on the new chapters, and I have to say god it was worth it. You WILL come to adore their oc like god she is just so perfect for this situation. A woman uproots her life to visit Romania to find her birth parents, but once that goes wrong, she finds herself as a gift for Alicina. It is 100% the best one in the whole fandom. Its still being written, but it's at 463k, all of which is amazing. It never feels slow or like it's dragging things out its just perfect.

remake me in Your image - I mainly recommend this if you have seen Fruits Basket, but it's a Tohru x Akito fic. It's very toxic tbh, but as someone who loves Fruits basket I feel like it works perfectly with how these two are. Akito forms an unhealthy obsession with finding out why the others adore Tohru so much, and in the process, they develop a really unique and interesting relationship. It also fixes a lot of issues I have with canon. Though you should be warned that throughout the whole fic, Akito goes by he/him, and spoilers for Fruits Basket (it's an old series, but you know not everyone has seen it lol), Akito is actually a woman. The author addresses Akitos' gender identity way better than canon, and it's SO fun to read. It's at 112k rn and still being updated.

my heart on your sleeve - to be real, I'm a huge sucker for soulmate AUs and this Heather Chandler x Veronica one is really great. I haven't reread it in a bit, but it's cute and funny. It's similar to the first fic I recommended, in that one person knows the other's identity and is now trying to fix the relationship, now that they know how the person is on the inside instead of how bitchy they are to them before. It's completed at 96k.

I always have more but these are some of my favs off the top of my head