User blog comment:B214/High School DxD EX/@comment-27083298-20170415041321/@comment-120.188.65.0-20170416191340

Eh, i think it was mentioned in Vol 4 that Michael is the only Archangel. Gabriel, Uriel, and Raphael are called Four Great Seraph, while Metatron, Sandalphon, Ragiel, Raziel, etc are called Ten Great Seraph