Fellowship of Freelancers
joined Oct 11, 2010
I feel like the subplot with Yukari was referencing something I'm not aware of.
My only guess is that Yohane's Yukari is in love with Yuyuko as shown in, er, "previous" doujins. Whether it's mutual or not is up in the air, but most likely it's not.
I figured Yukari wanted chocolate from Reimu, and she told Marisa about Valentine's Day so Marisa would end up flustering Reimu.