VMS
From OS-Tan Collections Wiki
OpenVMS, aka VMS or Virtual Memory System, is the name of a high-end computer server OS that runs on the VAX and Alpha families of computers, developed by Digital Equipment Corporation. It is now owned by Hewlett-Packard, and can run on the Intel Itanium CPU. VMS is highly secure and excellent at clustered networking, which gives this OS a disaster-proof reputation that has lasted for over 30 years.
VMS-tan has several drawn depictions; These are in fact the same character at different ages.
See also: