Butterfly on Desktop is a trojan created to trick the user's friends that there are butterflies on the desktop. The trojan is also a butterfly simulation of how butterflies move in real life. The little flying insects may be cute, but the Malware is annoying and dangerous.
Once the user downloads Butterfly on Desktop, the user can choose how many butterflies the user wants on the screen. The butterflies are pieces of code collecting data from the user's desktop. When one of the butterflies freeze, that's them collecting the user's data.
There is no option to turn off the butterflies so they will be stuck on the user's desktop. Since the trojan blocks Task Manager, Task Manager will not be able to stop the trojan. Uninstalling deletes the butterflies but the virus stays on the user's desktop. Using normal anti-virus and anti-malware programs should be able to get rid of the infection.