Here are some phanfics that I recommend on Wattpad and Fanfiction.net. Most of these are E/C with some Erik/OC and Erik x reader. There is also a R/C phanfic on this list, too.
-The Phantom Ascending by @olivesky (Wattpad)
-A Phantom Christmas Carolby @CharlesToth (Wattpad)
-The Man Behind the Mask by @Christinedestler1 (Wattpad)
- Phantom of the Opera Text Messages by @TheMJ1955 (Wattpad)
-A True Angel by @TaylorisaPOTOFan (Wattpad)
-Pen A Pal by @LJangel527 (Wattpad)
-E/C One Shots by @nightmare_carousel (Wattpad)
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-The Man Behind the Monster by @lukesagoodboy (Wattpad)
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-The Phantom of my Heart by @butterflygurlll15
(Wattpad)
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-My Angel by rororogers (Fanfiction.net)
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-Her Story by GoldenLyre (Fanfiction.net)
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-How Phantom of the Opera Should Have Ended by @Funk As Puck (Wattpad)
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-No Dreams In Her Heart But Dreams of Love by Christine de Nuit (Fanfiction.net)
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-POTO One Shots by @PhantomLover2000 (Wattpad)
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-Unexpected Life by @hannahdestler (Wattpad)
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-Dreams Came True by @hannahdestler (Wattpad)
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-Happily Ever...Phantom? by @LoveQueenElsa (Wattpad)
-The Phantomous Tales of the Phantastic Phantom by @therealprimmadonna (Wattpad)
-Our Love Is Evergreen by @BrendaDaaeDestler (Wattpad)
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-Every Waking Moment by @ChristineDaae1881 (Wattpad)
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-The Phantom of the Phantom of the Opera by @BrendaDaaeDestler & @EmmaMarchAdams (Wattpad)
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-Hear My Voice by @TheSwedishSoprano (Wattpad)
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-In Dreams She Came by @BrendaDaaeDestler & @EmmaMarchAdams (Wattpad)
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-Never Learn To Be Lonely by loveyou232 (Wattpad)
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-My Angel of Music by @Christine__Daae(Wattpad)
-The Man Behind the Monster by @Hawkfrostlover13
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-I Love You, My Angel by @ cornelia-phantom (Wattpad)
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-Phantom Christmas Story by @Destler_Erik (Wattpad)
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and then Add to home screen.