According to toukaikitune:
Triangle “Triangle Love Letter”
This video broadcast on 1978.
“Triangle Love Letter” is their debut tune.Members:
L: micchi (MORI Mitsuko)
C: ku-ko (OTSUKA Kuniko)
R: mami (UENO Mayumi)When huge idol group “Candies” retires, they announce the group name “Candies Junior”.
However, it is protested by fans of “Candies”.
They rename the group name to “Triangle”.
And, they debuted.
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