Blowfish.dll is a ransomware .dll file.
It is currently known as its own type of ransomware. Its purpose and creator are unknown. It currently has no payload and may not activate. It may just be a stray file but when scanned by an antivirus, it is treated as a High Level Threat. It's still obscure and potentially harmless.
However precautions should be taken and immediate removal after detection is advised as it may encrypt your files. If encryption does occur, there's currently no way to decrypt your files unless a backup is recovered.
It goes under the name of Ransom.Cerber in