akikan40
While discarding the members of his noble is wrong, Riser can deliver them to his queen Yubelluna. Yubelluna should already have the power of a middle class devil, then get the evil pieces and exchange them with all the components of the Riser nobility (except her sister) thus obtaining new pieces to have new members in her harem .... cough ( Ingvild Leviathan, Rosweisse, Valerie) ... cough ...
Top 50 in the world? I really hope that's Riser just being an unreliable narrator, because he shouldn't be even remotely close with just what he has so far. Forget 9x, Even 100x Start of Canon Riser isn't reaching that level on a world wide scale. Just the Three Factions? Maybe. World Ranking? Definitely not. DxD actually has A Lot of strong characters, both canon and just implied to exist by virtue of being an 'all supernatural is real' type world.