Here’s Manatsu route Summary. He has three endings as well. A best end, good end, and bad end. I should mention that you can’t get his last CG until you complete Asagi’s route and redo his best end. ((which I haven’t done yet. psh.))
Serigano Manatsu runs a shop that Gin often receives food ingredient deliveries from. He’s a gentle, kindhearted man who also has a soft spot for Suzuri. He’s apparently Suzuri’s uncle and his sister who died was the woman that Gin loved and had Suzuri with. He’s all clumsy like since when he rides his motorcycle he always ends up crashing it. He’s voiced by Kazuyuki Okitsu.