I've loved a lot of anime OPs! Let's see, my favourites are probably:
Ao no Exorcist OP1 (Core Pride) & OP2 (In My World)
Bleach OP2 (D-tecnoLife) & OP10 (Shōjo S)
Full Metal Alchemist: Brotherhood OP1 (Again)
Death Note OP2 (What's Up, People?!)
One of my absolute favorites too! I never skipped that opening and it's amazing how she can play with her voice.
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