Air Groove is cosplaying as a recently released (as of the posting of this comment) character from Sennen Sensou Aigis who has an uncanny resemblance to Air Groove.

tehSandwich said in comment #2630409:

Air Groove is cosplaying as a recently released (as of the posting of this comment) character from Sennen Sensou Aigis who has an uncanny resemblance to Air Groove.
asset #50062405

JP been calling her Quasilegal Air Groove and she's trending on social media as 脱法エアグルーヴ. Yeah, can't believe they just copy-pasted Air Groove's facial features with the exact same facial expression and hand gesture.

Funnily enough the character is also a genderbent version of Karasuma Ayamaro from The Yagyu Clan Conspiracy (TV series version). You might have heard of the original movie version starring Sonny Chiba that was renamed Shogun's Samurai as the English title.

Anyway the character looks like this:

...and holds the same position as commander of the imperial guards (well "minor general" instead of "major general"). He's also a scary conniving bastard, kinda like an effeminate Cardinal Richelieu but also with the martial skills to back it up. Imagine Richelieu with the combined fighting skills of both Jussac and Rochefort, yeah.

Now in-story he's scary but out of context he's gets endlessly memed because of all his exaggerated facial expressions and bombastic lines.