Nagisa & Tomoya
Ok, so I feel like this goes without saying, Clannad is the best slice of life anime series ever. It has everything you could ever want in an amazing show and Clannad hits home with so many things that we deal with on a regular basis. Family, friends, downfalls, death, depression, happiness, basically everything. The relationship between Nagisa and Tomoya grows throughout the show and you watch them fall in love. The emotions portrayed by the voice actors is great and I couldn't have asked for a better series. Seriously, amazing. If you haven't seen this anime, I highly recommend it.
Kirito & Asuna
This is probably one of the most popular ships in anime history and I honestly love it. Their chemistry is undeniable. I feel like the romance was sped up a bit in the series, but that's understandable due to the dyer situation they were in. Kirito had already lost one love and we saw the pain that inflicted, then when he met Asuna he was hesitant on opening his heart again. What sprung from that was an incredible story of love, heartache, and will to survive.
Taiga & Ryuuji (Tiger & Dragon)
Probably one of the most dysfunctional relationships I've ever seen, but these two have so much love for each other. Ryuuji was there for Taiga when she had no one and Taiga made Ryuuji stronger by constantly encouraging him to step out of his comfort zone and take chances. Their friendship blossomed into love and their character development with one another is so in depth and spot on. Love, love, love these two.
Nanami & Tomoe
These two were meant for each other. Nanami went from being a nuisance in Tomoe's life to being the most important being to him. Nanami calls Tomoe out on his bullshit and Tomoe isn't scared to hurt her feelings because in the end they'll just end up forgiving one another. I loved watching their love unfold and all their hilarious moments. I could re-watch this series over and over again. Bravo TMS Productions. I'm forever grateful to you for this work of art.
Banri & Kouko
These two really get to me. In my opinion, it's one of the most realistic relationships in anime. Banri, who struggles with amnesia and Koko who has attachment issues, meet and fall in love, but it's not instant. While Koko deals with losing an ex, Banri tries to remember his past life. They meet and both come to realize the hardships of love, but push through it together.
There are so many more that I haven't mentioned, so I'll more than likely make another list soon! Thanks for reading!