Three years ago, Serizawa was troubled with about his psychic powers. One day, he was visited by the boss, Suzuki Toichiro. Serizawa ends up trusting him since he's the first person to understand what he's going through. But Mob then brings up the fact that Serizawa is being used and tells him, "I'll be your friend." Hearing Mob say that, Serizawa... 

Meanwhile, after defeating Sho, the boss starts gathering up the energy he was sharing with his followers and turns into an energy monster.
On top of that, he's got
a massive stock of energy himself.
وعلاوةً على ذلك، لديه مخزون كبير من الطاقة
Außerdem hat er eine
Riesenmenge angesammelt.
Por si fuera poco,
tiene una buena reserva.
Por si fuera poco,
tiene una buena reserva.
Du coup,
il en a accumulé un gros stock.
Non solo, ne ha anche una gran bella riserva.
Além disso, ele tem uma 
quantidade decente de energia.
Мало того, у него её просто
чудовищный запас.