Board Thread:General Discussion/@comment-24319911-20160701130131/@comment-25549954-20160719104401

. . . . @Sunou-san it was only because of Tatsumaki that we have come to know that Blast had same costume and he called himself Blast.
 * Webcomic Spoiler* If you haven't read webcomic

I think Blast is some other kind of psychic human being, the reason behind his name could be that he had some kind of power like explosion, I wouldn't be surprised if he turns out to be esper like Mob (from Mob Psycho 100) and that is why Tatsumaki admires him so much when he rescued her.