Ruchka is a collaboration between Kayoko Sato and Satako Sasaki. The word "ruchka" means "pen" in Russian. Kayoko Sato is the owner of Kirarasha, a shop that sells mineral specimens and other science-related goods. The shop also includes a café and holds various science workshops. Kayoko Sato previously worked as an elementary school teacher and science club adviser. She loves performing experiments and reading about science. Visit her website at kirara-sha.com and follow her on Instagram @cafesaya. Satoko Sasaki is an artist who works under the name Sasakisa. She specializes in manga and watercolor illustrations inspired by nostalgia, natural science, and fantasy. Visit her website at junk-club.net and follow her on Instagram @toko_ssks.