Either ones that were based off of the work or just remind me of them

Death Note:

• Watch Out, You're Being Watched Now
• I Can't Decide by Scissor Sisters
• It's Tough to Be a God (haha, when really you're a sham!)
• Secret by the Pierces (the secret is that Light is Kira)
• Busted from Phineas and Ferb (L is going to bust Kira)
• Brand New Day (various story bits)
• Playing God by Paramore (Light is playing God)

A Rose For Emily:

• A Rose for Emily by the Zombies
• Preserved Roses by Blackbriar

Wuthering Heights:

• Wuthering Heights by Kate Bush
• Super Psycho Love by Simon Curtis
• I'm in Love with a Monster by Fifth Harmony

Alice in Wonderland:

• Her Name is Alice by Shinedown
• Hey Alice by Rachel Rose Mitchell
• Alice in Wonderland by Avril Lavigne
• Tea Party by Kerli
• We're All Mad Here by Emma Wallace
• Rabbit Hole by Emma Wallace

Fruits Basket:

• It's Tough to be a God (Akito)
• I Hate Everything About You (Akito)
• Monster by Imagine Dragons (Kyo)
• Anything You Can Do I Can Do Better (Yuki and Kyo)
• Happy by MatD (various couples)
• Immortal by MatD (Akito and some others)
• Dismissed by ZOEgirl (some of Juunishi to Akito after curse)
• I Enjoy Being a Girl (Kimi Toudou)
• Rootless by MatD (Tohru pre-story)
• Guilty by MatD (Kyo)
• Playing God (Akito)
• Mz Hyde by Hailstorm (sort of fits Hatsuharu or Kagura)
• Devil in Disguise (Kagura and esp. Shigure!)
• After the Winter by Lenka (Hatori, "When the snow melts, what does it become?")
• Monsters by Lenka (Kyo)
• Paint It Black (Hanajima)

Ouran:

• It's Tough to be a God (Host Club)
• I Just Can't Wait to be King (Tamaki)

A Murder is Announced:

• Secret by the Pierces

Carmilla:

• Vampire by Xandria

Lolita:

• Lolita by Lana Del Rey

Rocky & Bullwinkle:

• When You're Evil (Boris)

Phineas & Ferb:

• When You're Evil (Dr. Doof)

Fullmetal Alchemist/Brotherhood:

• When You're Evil (Homunculi, esp. Envy)
• It's Just Me (Envy)

Sleeping Beauty:

• When You're Evil (Maleficent)

Valley of the Dolls:

• Valley of the Dolls by MatD

Puella Magi Madoka Magica:

• White Rabbit by Egypt Central
• Dark Paradise by Lana Del Rey
• The Witching Hour by Rachel Rose Mitchell

Akuma No Riddle:

• Mz. Hyde (Banba)

Mean Girls:

• Pit of Vipers by Simon Curtis

Arisa:

• Pit of Vipers by Simon Curtis

Baccano!:

• I'm in Love (With a Killer) (Lua and Ladd, Chane and Claire/Vino/The Rail Tracer)

The Future Diary

• Mz. Hyde (Yuno Gasai!)
• Punchin' Bag (Yuno Gasai)
• Gorgeous Nightmare (Yuno and Yuki)
• Super Psycho Love (Yuno to Yuki)
• Time for Tea by Emilie Autumn (Yuno)
• Babydoll Gone Wrong (Yuno)
• Sweet Serial Killer (Yuno)
• Terrible Things by April Smith (Yuno)
• Are You Afraid by Steampianist & Zip Zipper (Yuno)
• Machine Gun by Kira (Yuno)

Danganronpa

• Terrible Things by April Smith (Junko)
• I'm The Bad Guy (Junko)
• When You're Evil (Junko)
• Get Jinxed (Junko)
• Are You Afraid by Steampianist & Zip Zipper (Junko and Mukuro)
• Discord by The Living Tombstone
• Gifted by Athena Z (Hajime Hinata)
• Queen of White Lies (Celestia Ludenberg)

Higurashi:

• Are You Afraid by Steampianist & Zip Zipper
• Pit of Vipers by Simon Curtis (The Three Families, esp. the Sonozaki clan)
• Queen of the Castle by Victoria Carbol (Takano)

1984:

• Propaganda by Crusher-P

Pride and Prejudice:

• Excuse My French by Caro Emerald

Umineko:

• Queen of the Castle by Victoria Carbol (Beatrice)