Cat Incision Question

My cat had surgery the end of February. He healed well and seems great. I was just looking at the incision and it red around the bottom. I'm not sure if it's a concern or not because his skin does fold together there and it could look like that on a regular basis but fur typically covers it (they shaved his belly for surgery of course). I'll post pictures so you all can help better. I'm new here so bare with me please