User blog comment:Crimson lotus ichinose/Can Mika use his Seraph form?!/@comment-36009152-20191129223012

This may be a clue as to what direction the story is leading, perhaps Mika is to be a seraph in which case his vampire status could be removed, or Shikama Doji can force the change anyway.

Alternatively if everyone becomes a vampire, at least that is hopefully a means to an end of preventing more world ending seraphs from becoming active.

Mika may very well be pleased that a seraph gene could have no influence on him!