I think they were just acquaintances and maybe they are new friends now since they recorded together. What I know is they met the first time in February 2016 during the kansai collection show. I think Kondo was there as a model and perhaps as a fashion designer too while Vell took part to the event as a singer. She had shared pics on twitter at that time :
That's possible that Youtube linked them because they were at the same event, both debuted the same year under Avex and they have a similar style (both are crazy).
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