Well, I don't think they're technically J-Pop, but I recommend Cibo Matto. Their sound is kinda quirky. Many times, they use traditional Japanese sounds, and combine them with a broad mix of other genres. I dunno. They're weird...in a different way than your average J-Pop. Their music is obviously influenced by some American music. My favorite song by them is "Apple." If you like them, I'd also recommend Buffalo Daughter.
Also, I like Takako Minekawa. She's probably closer to what you'd expect from a J-Pop artist, but she's got some cool songs. I have her album, Fun 9. My favorite song on it is "Tiger."
Hope that helps!
"I don't judge people. I just watch them til it's time to look away. I wanna look away now."
-Kristin Hersh, "Your Dirty Answer"
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