The anime is about two brothers and a girl who have guardian spirits.
The girl was almost hit by a truck when her guardian spirit awakened and protected her.
But the story is mainly about two brothers the older one was able to bring out his guardian spirit and the younger brother wasn’t, the older brother was forcibly taken to some school in the middle of the ocean from where none of the students were ever able to escape till graduation. He becomes the first to escape by jumping into the ocean and swimming through it to the other side and goes back to his brother. Then they were attacked by bad guys and the older brother died and his guardian spirit sacrifice s himself to awaken 5 guardian spirits of younger brother. Their duty is to protect some sacred tree (if I’m not wrong) and the older brother becomes a ghost and younger bro grows up and becomes a delivery boy while protecting the tree ig.
( This is the story but it’s a bit jumbled up because I watched it a while back can u guys help me find the name of the anime)
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