Wench.2537 is a encrypted, not-polymorphic, not-resident DOS EXE file infector.
When Wench (or a file infected by it) it's run, Wench will infect only the first EXE file that's not infected and that's found in the current directory, until every EXE file in the current folder is infected. The virus is buggy, and sometimes hangs, or skips files. Every June 17, of every year, the malware will display a graphical effect; the following string will be present over the screen:
Yaunch + Wench
The virus is not dangerous.