Comment by Charles Honkai 3rd Player on Lucairian

No, 

yuuki survives, this is manga is adapting volume 10 rn, around volume 22, yuuki is still alive, but yuuki aint a villain anymore at that point,

this is another spoiler be warned

mariabell becomes a skill in volume 22, and yuuki was forced to listen to her as, mariabelle is like raphael to yuuki now, his new power is a curse on itself, becuase, he cant get rid of maria, and maria annoys yuuki at everyturn

yuuki asks rimuru for help, rimuru says, thats what you get, and thats the punishement that u deserve