The author's name written on the front page of the manga is definitely Okuda Waku. Ogawa Chise's name is spelled "緒川千世."
I read somewhere that Ogawa Chise and Okuda Waku are twin sisters, I don't know if that's right...
the author's sister is morie satoshi
and believe me, their drawing is so similar so much that it looks like ogawa chise draws shoujo mangas (morie satoshi is a shoujo mangaka) https://twitter.com/morinotes
i thought the author is ogawa chise..... no?