Today, the mini-test "Which Touhou Character Are You?" went viral in various QQ groups. As a proud CS student and the organizer of a Touhou doujin circle, I couldn't help but wonder: How does this test actually work? Does it truly use machine learning to match characters, or is it just simple conditional logic? Is my intuition about a "six-dimensional vector" matching actually correct?

To solve this mystery, I analyzed the source code of the webpage. In this article, I will take you deep into the code to see how your "soul character" is actually calculated.

The Peking University (PKU) Touhou meeting on November 23, 2025, was the first offline debut of our circle's products.

For this occasion, we specially prepared two prints of Yukari-sama. According to the original script, the 16-inch print was for the lucky draw, while the 20-inch one was only for display. However, due to a failure to confirm details with the staff, something unexpected happened—the 20-inch masterpiece, which should have come home with me, was held high by Remilia on stage and given away as the grand prize to a lucky "villager."

What's done is done. To avoid disappointing everyone, I decided to "go with the flow" and gave the remaining 16-inch print to the hardworking staff members on site.

The promotion cost for this event completely exceeded the budget, but participating in a university meeting with such a great atmosphere was definitely worth it. Moreover, I had a burst of my own luck and won a second prize—Enjou Bookstore's "Human Village, Strolling in the Courtyard."

At the Beijing THO on November 8, 2025, I saw three stunning Touhou-themed famous painting parodies. After buying two of them, I was still amazed by the creativity and wanted more.