Ah, Remus. James loves you tremendously. I'm sure he pouts to Remy on occasion because, of the Marauders, Remus is closest to Lily. He's holding out hope that Lily will come around. It may take some growing up on James' part and exerting himself to pursuing her all over again, but he's gonna try at any rate. Remus/Tonks love all around, though, and James promises to try not to sulk and be reminded of Evans when he sees their budding romance. ;D
I'm planning on starting up some backstory stuff ASAP, so if anything strikes your fancy or you have some ideas lemme know!