Code: Breaker

Code: Breaker is a shonen manga which centers around a high school student Sakurakouji Sakura.

Riding the bus one day, Sakurakouji Sakura looks out the window to see people being burned alive with a blue fire and a boy her age who's unharmed and standing over the people. She comes back to the site the next day and there are no corpses or evidence of any kind of murder, just a small fire. She then goes to class to find there's a new transfer student who looks exactly like the boy she saw before and wears a black glove only on his left hand who is Oogami Rei. Oogami is a Code Breaker, one who "does not exist". He is a seemingly cold-blooded killer who follows the principle of "an eye for an eye", to "use evil against evil". Convinced that killing is not right, Sakurakouji sets out to stop him and penetrate his icy heart.

And every chapter introduces a lot of new characters, like Toki, and other Code: Breakers eventually. Some of the side characters too have interesting effects to the story. If you are interested in mangas such as this, then go grab the latest issues near you or you might as well look for other alternatives if its not available in your area (like mine, so sad).