User blog comment:Jopjopjop/SlashDog/@comment-50.139.232.230-20151007013013/@comment-26527700-20151009215241

For them to appear in Slashdog, Slashdog would have to catch up to DxD in chronology, since the locations of those Longinus are unknown as of DxD. Alternatively, it might be possible if the wielder were to die between Slashdog and DxD.