User blog comment:Jopjopjop/Volume 20 Spoilers/@comment-178.128.252.204-20150825183711/@comment-24421137-20150825202026

No. The king piece is illegal so why would it replace any of Issei's pawn pieces. Also the king piece is used externally, unlike regular pieces, this piece only used as sort of like an equipment to boost the power of a team mate.