|Full Name||Citation needed|
This is an article about the 3.1-tan OS-tan. To learn more about the OS she personifies, or see more characters that personifies that OS, see Windows 3.1
3.1-tan (Japanese: 3.1たん, 3.1-tan), also known as Ōbaba (Japanese: 大婆), or Citation needed, is the OS-tan that depicts Windows 3.0 - 3.11. She is one of the lesser known OS-tans.
She is the younger sister of 1.0-tan, the older sister of 3.1-kun and NT-Mama, and the mother of 95-tan. She has an inseparable relationship with DOS Kitty since Windows 3.0x is heavily reliant on DOS. After the OS wars with Mac OS she retired to live in the OS family shrine. Previously, it was assumed that 3.1-tan would have been a civilian on the sidelines of the OS Wars but new images of 3.1-tan in military uniforms and holding a sword imply a different character interpretation: that she may have played a more actively part in the wars.