I've been reading more Japanese literature, and in doing so I've come across hiragana with something that looks like 、to the right of some characters where ふりがな would be (keeping in mind that Japanese is written from top to bottom in books. It's not a comma, and it seems to usually appears on hiragana in succession.

I was thinking it was for emphasis, something like italics, but don't know what it means for certain.

I've attached a picture to clear up any confusion as to what it looks like. They're on the very right of the image by 「いわし」.

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