Okay. So. It's set in Japan (obviously xp) but it's also kina futuristic (not flying cars futuristic, more like...Holorgram watches futuristic) and there are certain people who have this superpower that is basically an Aura. Each Aura has it's own powers (Red = Fire, Green = Phase, etc.) and those aura/colors have their own unique "clans", each clan has a King that can distribute his/her/it's aura to another person. But some people (or even animals) don't need a king too have their own aura/power, those people are called "Strains".

Now, as for what's going on (now this is where it's gets really complicated, so time to use your Highschool Queen Bee Gossip Brain): HOMRA (red can) is after a guy named "Yashiro" and Yashiro has no idea why, and SEPTER 4 (blue can) is trying to stop both (since blue clan is basically a police department) and a ponytailed swordsman saves Yashiro from both clans , now Yashiro is accused for a crime he didn't commit and is trying to prove his innocence...And the story will unfold as the episodes continue.

Awwww, don't be nervous x3 Silly thing. hugs