Well, without more context, it's hard to say exactly. But generally, in many stories involving a king and a lyre, the lyre could symbolize art, culture, or a connection to the divine. The king might be associated with the lyre as a sign of his refined taste or as a tool for his leadership. For example, in some ancient tales, a king's ability to play the lyre well was seen as a mark of his wisdom and suitability to rule. It could also be a story of how the lyre came into the king's possession, perhaps through a heroic quest or a gift from a powerful being.
A 'lyre visual novel' could be a visual novel that perhaps has some connection to the lyre, an ancient musical instrument. It might be a story where the lyre plays a significant role, like in the setting, the plot, or as a symbol for the characters.
Since we don't have the full details of the 'king lyre story', we can only speculate. The king is the central figure, no doubt. There could be a master lyre - maker who crafted the special lyre in the story. There might also be characters like the king's enemies who either covet the lyre or are threatened by the king's possession of it. And perhaps there are characters from the king's family, like his heir or his queen, who are also involved in the events related to the lyre in some way.
It could be a tale of unexpected meetings and growing affections. Maybe they face challenges that test their bond but ultimately find a way to stay together.
I don't have the exact name of the person who created the Omori manga at hand. It could be worth doing a search on manga databases or asking fellow manga enthusiasts for the answer.
Omori is purely fictional. The story and characters were imagined by the creators, not drawn from real-life events. It offers a fantastical and imaginative experience for players.