Tsukumizu Yuu (a pseudoname) is a manga artist and an illustrator. They're known for authoring Shimeji Simulation, Girls Last Tour, and various not-so-known doujins such as Flan Wants to Die and others.
What we know:
There is a possibility that Tsukumizu wears glasses. That's just a speculation, though.
They had a dog named Gon in their parents' home, but Gon disappeared and wasn't found before they finished GLT.
They live in a room with walls made from concrete.
They were probably ashamed of their identity on the Internet when the popularity struck (see some of their earlier tweets). That's probably why they deleted the Pixiv account and purged their Twitter.
I started to write manga during my second year of university. Around the end of university I was invited into a friend’s manga circle. My works from there were uploaded to the internet and someone from Shinchosha noticed, which lead to my debut. So I wasn’t working for very long on doujin. I worked on these sorts of derivative works during university, but ‘Girl’s Last Tour’ is my first original work.
I originally liked reading novels, so I read a lot during elementary, middle and high school. When I got to my third year of high school I began to enjoy drawing, so I started drawing rather normal moe drawings. This lead me to start writing manga.
Noteworthy posts on social media
Compilation of Tsukumizu's GIFs. The tweet was supposedly made around the time Tsukumizu deleted their Tumblr account with all the GIFs.