I said I'll translate forum posts about ZUN's manga writing and why he chose Harukawa. There's no real source about the latter topic; all that exist are meaningless gossips. On the former topic, the Japanese forums do discuss how ZUN writes manga a lot, but the more they discuss, the more confused themselves seem to have become. Nonetheless, certain things appear to have some basis in reality.
The summary below is based on ZUN's twitter, some Touhou fans' tweets, and forum posts. The Japanese fans may have got some of their info from previous Nikenme Radio broadcasts.
- First, ZUN writes the script of a manga chapter. He calls it プロット using the English word "plot", and sometimes refers to it as 原稿 "manuscript".
- This so-called "plot" actually contains extremely detailed instruction on everything, to a degree rarely seen in the manga business. People have advised him it's unnecessary, and he should have left things for the artists to decide, but he wouldn't listen.
- His effort is such that he even designed all the extra kappa girls in WaHH himself. It's highly likely that all the character cameos in manga are arranged by ZUN, so you should never question their canonicity again.
- Having finished the "plot", he attends a 打ち合せ "business meeting" with his editor and artist in a pub. According to Harukawa's comment on the FS Vol. 1 jacket, even her pen name was decided upon in a pub.
- After the script is delivered, ZUN falls into radio silence. He does not oversee the creation of the art at all, no phone call to the editor or the artist. Regarding how this chapter turns out, he would prefer to wait and see the magazine himself.
- Another thing to note: Generally ZUN calls his writing work for book publishers 仕事 meaning "work" in the sense of "doing the job", and his own game-making 作業 meaning the operation/process of working.
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Some info from March 28's Nikenme Radio:
- When talking about times of the day suitable for game development, ZUN quoted the famous opening passages of the
Pillow Book: "In summer, the night is the best. In spring, the morning."
- WaHH Vol. 3's release date was set to July because they needed to manufacture the figurine.
- When he was a child, ZUN used to do some cleaning work for shrine(s) and Buddhist temple(s) on Sunday morning. The monks gave him a lot of things, so he liked the temple(s).
- He likes the
Heart Sutra, using its chanting as background music.
- Lord of Vermilion 3 (
that collectible card arcade game from Square Enix) will have ZUN's collaboration again, most likely meaning it'll feature more Touhou character cards with flavor text written by him. By the way, Yuuichi Tanzawa appears to be a project lead on this game.
From April 24's Nikenme Radio:
- One year ago, ZUN wanted to get in touch with new things, and tried to play Puzzle & Dragons (highest-grossing mobile game of the world). These kinds of 作業ゲー (games that demand so much time they may as well be work) are not to his taste.
- Okonogi (his editor) wondered why both ZUN and his wife love frogs. [ki-san really, really loves frogs.] ZUN said: "I love frogs. They are delicious."
- At the end, ZUN said: "This time I'm going to cinema, for real!" He haven't been going out much due to developing the new game, you know.
