#794.89

[your-dewey-decimal-number-is]

Where would rhythm games go? Is there a games about music section?

There's no section for musical games specifically, though there are section for sports games (794.86), flight simulators (794.87), and fishing/hunting games (794.89), so your best bet would be to look in 794.82 (video games by genre) or 794.85 (specific video games)