So, it goes like this:

Dr Willy has created a proto named Blankspace Man, but in the minute he was developing the biomaterials to make him stronger, Blankspace Man shoots him and erase all of his memories.

A few seconds after that, with all the guilt in his shoulders, he decides to shoot himself so he could forget everything, but the brain... the brain is a nasty organ.

He succedded in his task of deleting his memories, but he couldn't delete the feelings, so, like a natural thing, he's wandering around the world deleting memories and re-configurating his brain, in a constant loop of pain and danger.

¿Can Megaman stop this madness?

What?... Wait...

I forgot what I was going to tell you...