Sigma decided to touch Fyodor - since his ability was to find out all the information he wants from someone by touching them, but so does the other person. Knowing that might be the last choice of his life since Fyodor's ability can kill someone by touching them. Fyodor asks him what he wants to know and he says "all of your secrets". They touch and Sigma feels a huge flow of information going through him. He faints and Dazai goes to search for him.