Yep, Iky, he's a nosy teenager. It's hard at times, but try to remember that "decent" is a purely human boundary as far as physical behaviour goes. If you'll correct him and let him know you don't like it he should stop. It may take time and consistency, especially if Codi's as 'focused' as I suspect he is. :wink:
Remember, too, that his breed is a highly social breed and sniffing is a canine form of social intimacy. At this stage in his development, Codi probably doesn't understand why you don't want to sniff him! He's also feeling lonely sometimes, too, I suspect. They remember and miss each other far longer than many give them credit for. Our Buffy's been gone for over two years now, and Bimmer still acts listless if we talk about her too much in front of him, moaning and dropping his ears and tail. It breaks my heart to see him, but Kharma typically walks over to him with her big butt swinging back and forth, head lowered, and licks his face until he starts washing her face - just like he did Buffy's.
Codi's going to be experiencing many changes; between hitting puberty and dealing with losing Buddy he's on a doggy roller coaster right now. Just be consistent with him. It will not only help you deal with him, it will help him cope, grow up and carry on to have a happy life.