Hi guys, I came across something in a novel I'm reading that for the life of me I can't compute:
二人が少し遅れて公民館に到着すると、仕事前に集まった「ムウジカ」の人たちや、
サンバ姉さんこと清寺由紀江たちがすでに来ており、派手な音楽に腰を振っていた。
It's the こと of 「サンバ姉さんこと清寺由紀江たち」, I'm not sure what it's doing here. After looking up 「姉さんこと」on google it does appear quite a bit, but I'm still not sure of its function. I can only think it has some sort of grouping function, like "The samba girls of 清寺由紀江" or something.
Any help would be greatly appreciated!