OverBooruAdmin: His name is "Glittering Angel Neko Nyan," and he is from the world of Overlord. The energy embedded in the eye of Pantagruel — a holy knight of the tank profession who transferred to this world with a strategic golem — is an item called "Goro Nyan the Great" which Neko Nyan brought with her, but the doctor misheard it as "Coronatite". According to Overlord's Mr. Maruyama, in his original world he had a harem and already had children. Maybe more references will be made in the Overlord weekly specials. The special novel "Neko Neko Neko Nyan" is also about this Neko Nyan.

From the overlord discord, the armor certainly looks like a male version of the one in the v16 cover.