If... you'll get a best friend... Will you choose an extraordinary one? Or the normal delinquent one?

This one's fictional.

Glenn, a.k.a Sato Mai, struggles to get her mother a revenge.

Yamada Ryosuke, a happy go lucky idol who meets Glenn as Sato Mai.

Ryosuke shares every event of his life to Glenn... But what if, he discovers his long time geek best girl friend has her admirer? What's worse is that she kept it as a secret? And just as he does, he finds himself hurt?

Glenn as someone who carries the burden as their family's heir, she struggles to get her motherrevenge. At the age of 12, her mother saves her life from a monster... Grieving on her mother's death brought her to the human world...where she needs to find the master mind of the massacre.