I'm Friends With A Monster ( 7 Deadly Sins color)

 if  Leons  twin brother return to normal  hes going to regret himself after leon saves him  from his inder demons   his eyes will trun to a purplish red  color of the 7 deadly sins those are surpost to be is inder demons for the background and light.

 the  reference is from  the song  Eminem - Monster ft. Rihanna