Others Summon Dragons, I Summon Legendary Knights Chapter 424

Isolde wakes from a vision of a shadowy being who calls himself an emperor and seems to be searching for a missing part of himself, asking who Frey is. She is unable to communicate this vision until she paints it, revealing the Unknown King. Godfrey recognizes the being and realizes it may be a part of himself that survived his own death, and Isolde interprets this as a clue to his future fate.