Mathias Luna Tearmoon is the current Emperor of the Tearmoon Empire and father to his only daughter, Mia. He's a harmless guy—by Mia's own account—but an embarrassingly devoted dad. His expressions of affection tend to get out of hand; his idea of punishment for Mia's recklessness was making her call him "dad" instead of "father" for nearly a year, much to her mortification. What matters to him above all is that Mia likes him, to the point where he genuinely doesn't care what the empire thinks.
As an Emperor, Mathias is middling at best. He tries his hardest to rule competently, but it wasn't enough to prevent a revolution or save him from execution. Public opinion of him stays pretty low. That said, he carries himself with real authority—there's something majestic and imposing about his presence that fits his station. He's also surprisingly sharp about security, keeping a careful eye on who enters and leaves the royal palace.
Mathias is fiercely loyal to family, especially to his late wife, Adelaide Luna Tearmoon. She died a few years after Mia was born, and he's never entertained the idea of remarrying or finding a replacement. Even though his mother arranged the match, Mathias has been clear: Adelaide is the only woman he's ever loved (not counting Mia), and it was love at first sight. He's said that if both he and Adelaide were drowning, he'd save her over Mia—which really underscores how deep that attachment goes.
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