Passage: Himouto! Umaru-chan (干物妹!うまるちゃん, Himōto! Umaru-chan) is a Japanese manga series by Sankaku Head. It began serialization in Shueisha's seinen manga magazine Weekly Young Jump on March 14, 2013. It has been collected in twelve tankōbon volumes. An alternative version was serialized for two chapters in Shueisha's monthly magazine Miracle Jump in 2012. An anime television series adaptation by Doga Kobo ran in Japan from July 9 to September 24, 2015. A video game was released for the PlayStation Vita on December 3, 2015. A second season titled Himouto! Umaru-chan R aired from October to December 2017, while a sequel series titled Himouto! Umaru-chan G began serialization in November 2017.

Question: Who wrote Umaru-Chan?
Sankaku Head