Sigma's ability allows him to exchange information with anyone he touches. The exchange consists of "giving" the person information they want to know, and thus giving Sigma the information he wants to know.
(From Bungostraydogs Wiki)
Just some canon facts about our favourite Bungou Stray Dogs Characters. Note: Bungou Stray Dogs is not mine... More
Sigma's ability allows him to exchange information with anyone he touches. The exchange consists of "giving" the person information they want to know, and thus giving Sigma the information he wants to know.
(From Bungostraydogs Wiki)