Wow! It's been a while for this one. Junko Yagami（八神純子）was one of the singers that I had first discovered through "Sounds of Japan", and during my two times in Japan as a resident, I managed to buy a number of her albums which reflected her early Latin influence and then her later R&B material.
However, the very first Yagami album I ever bought was an audiotape of "Yaga Mania"（ヤガマニア）at Wah Yueh, notable for that cover of her looking like she just saw a ghost...or me after a shower (yeah, like I wouldn't wish that on my 2nd-worst enemy). Before and since her 10th album, she's always looked rather sedate. But that wasn't the only interesting thing about "Yaga Mania" which came out in October 1986. Remembering how much heavy rotation I gave it on my tape recorder, especially during the all-night sessions getting those university papers ready, I think the album was a crossroads for Yagami. I don't recall any hint of her old bossa style in there, and there was a whole lot more of a pop/rock and R&B feeling.
Two singles came from the album, "Fun City" and "Chameleon", but the one that I've always associated with "Yaga Mania" has been the lead track, "Loser". Written and composed by Yagami, it starts off with something that sounds like a sputtery growly New Wave synth before another keyboard provides a more harmonic thrum and gives way to the familiar power of the singer's vocals. She may have been changing genres but the voice has remained constantly soaring. As she gives this tough-as-nails threat to her possibly erstwhile lover that if he leaves her, he's a loser, that voice slowly rises until that sonic boom I've known so well makes its appearance during the refrain.