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)
100Please respect copyright.ＰＥＮＡＮＡclnLO47ZK4
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-The Man Behind the Monster by @lukesagoodboy (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡSHf56BwA3k
-The Phantom of my Heart by @butterflygurlll15
(Wattpad)
100Please respect copyright.ＰＥＮＡＮＡU1fWLZewmc
-My Angel by rororogers (Fanfiction.net)
100Please respect copyright.ＰＥＮＡＮＡ0ToG1d9Wjw
-Her Story by GoldenLyre (Fanfiction.net)
100Please respect copyright.ＰＥＮＡＮＡhUE5bLPU5e
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-How Phantom of the Opera Should Have Ended by @Funk As Puck (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡlMxZeKLSN4
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-No Dreams In Her Heart But Dreams of Love by Christine de Nuit (Fanfiction.net)
100Please respect copyright.ＰＥＮＡＮＡp9qIzHpcPF
-POTO One Shots by @PhantomLover2000 (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡN5e6PbOq4B
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-Unexpected Life by @hannahdestler (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡc2OGntw6IA
-Dreams Came True by @hannahdestler (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡIAhnVx3Wuv
-Happily Ever...Phantom? by @LoveQueenElsa (Wattpad)
-The Phantomous Tales of the Phantastic Phantom by @therealprimmadonna (Wattpad)
-Our Love Is Evergreen by @BrendaDaaeDestler (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡI21cEEh0Xw
-Every Waking Moment by @ChristineDaae1881 (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡeCbpzh0BmL
-The Phantom of the Phantom of the Opera by @BrendaDaaeDestler & @EmmaMarchAdams (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡBtQfUN308l
-Hear My Voice by @TheSwedishSoprano (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡFOG1LmCv6r
-In Dreams She Came by @BrendaDaaeDestler & @EmmaMarchAdams (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡ3eMYHPNxf6
-Never Learn To Be Lonely by loveyou232 (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡ11RtYiTxsT
-My Angel of Music by @Christine__Daae(Wattpad)
-The Man Behind the Monster by @Hawkfrostlover13
100Please respect copyright.ＰＥＮＡＮＡKMvnqQoxPj
-I Love You, My Angel by @ cornelia-phantom (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡdBzGL5bbPx
-Phantom Christmas Story by @Destler_Erik (Wattpad)
100Please respect copyright.ＰＥＮＡＮＡ3PBpihHhOX
and then Add to home screen.