This is a parallel world just like ours but the difference is that here the concepts of monsters and other creatures is present here.
This story mainly revolves around a young man called Sam.He lives in blue star planet. this planet was attacked by monsters thousnads of years ago from then on some powerful people started to fight the monsters and they were clalled fighters.At present the monsters come to blue star for energy stones which is like food to them.
They can create worm holes from the different universes to any universe and search for energy stones.These worm holes are called monster tunnels in blue star planet.The powerful people fight against them and protect the people and planet.
To know about the different levels of mansters and fighters you need to read the book.I explained about the levels in chapter 4 but that is not the all.There are far more dengerous creatures in the cosmic sea.