User blog comment:JoAlter/Caster Gandharva/@comment-32751919-20191002103529/@comment-25848535-20191002161726

Waver-sensei: Karoshi, and proud.

Just remember this is altered timeline so his original self might not have been executed, probably died in other ways. And I don’t even know who is Lewis 🙄

He’s dead now, in the end of his storyline. Each servant will have their storylines which intertwined with others. So you may still see Caster featuring in Saber Yaksha storyline.