The One Within the Darkness

Ricky was a just your average boy with no special case just go happy boy with a happy family and school life..... Until his family was killed by a serial killer...He was famous for killing a families and raping, killing all the women and young girls then burning them to their deaths while still alive. He was terrorising the city..and no one have ever catch him or arrested him. After the deaths of his family he got a system which calls itself an angel. it promises him that it will help him to find his culprit... He wanted to take revenge that person who killed his whole family but he found out that it's not Simple as it seems... With him and help few of those survivors and his system plans to take out their culprit who is responsible for their misery.. How will they do it, what kind of conspiracy is this..will they be able to find him?? if they do what will they do??...Will the system really help him to find his culprit..or it's just a hoax..??