Saint

16 year-old Mishima Haruhi rescued a guy drowning in Yokohama Harbor, who has no memory of who he is or how he got there. Even more mysteriously, he seems to have extremely special powers including the ability to heal others. The only clue they have to his past is a bracelet he is wearing with the number "33" inscribed, but it is not long before people threatening to take his life force them to dig deeper...

(from mangaupdates)