CP/M was an operating system originally created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc. Created in 1974 as project by Dr. Kildall, it morphed into the flagship product of Digital Research. As times changed and the IBM PC became the industry standard, CP/M had to be modified. It became DR-DOS, a PC DOS-compatible operating system for IBM PC-compatible personal computers, originally developed by Gary Kildall's Digital Research and derived from CP/M-86.
DRDOS-tan (DRDOSたん) is one of the least common DOS personifications. She personifies CP/M, DR-DOS and its aliases. She is personified as a grey-haired woman in a doctor's uniform with glasses, long grey pigtails, teal eyes and CP/M hair clips. She is the mother of the DOS-tans and is GEM-tan's older sister. DR-DOS-tan is the oldest, wisest and tallest of the DOS-tans and works as a doctor for the vintage and DOS OS-tans she is affiliated with. Her services are free for the vintage OS-tans but very expensive for everyone else and does not seem to realize that the DR in her name stands for something else entirely, but that has not stopped her from practicing medicine, which she is excellent at. Her personality is laid-back and irreverent but also pleasant and motherly especially in the presence of her daughters. Although she always appears pleasant, she is not adverse to using her skills as punishment either.
It was not until recent years that DR-DOS-tan adopted the personality she has today, or the love for her daughters. Her very first friend was IMSAI 8080-tan who was at the time a powerful and megalomaniacal military engineer (The IMSAI 8080 was the first personal computer that used CP/M). DR-DOS-tan (then CP/M-tan) learned a lot from her but also picked up some unhealthy habits from her. DR-DOS-tan was entirely committed to her company and work, rarely had any contact with her daughters and in fact scorned QDOS-tan, MS-DOS-tan and PC-DOS-tan for years after they were born. But several years, company transitions, career paths and name aliases later, she reacquainted herself with her children who she now loves. She feels remorse for most of the things she has done in the past but still has some arguments with the more vocal DOS-tans (PC-DOS-tan, DOS/V-tan and PTS-DOS-tan). Ironically, she loves and cares for QDOS-tan precisely because she caused her the most harm from her absence, yet QDOS-tan is mentally incapable of showing anything but love to her. The guilt is to the point that DR-DOS-tan actually wishes QDOS-tan talked back to her like PC-DOS-tan does but as long as that's not possible, DR-DOS-tan simply does her best to make up for her parental negligence.