The nuchal hump depends a lot on temperament, tankmates, and genetics, especially in species like convicts and their close relative the HRP. My convict has only developed a nuchal hump when he had a female con in the tank with him. As a solo pet? Never. This is different from other species such as Midas who can commonly develop a nuchal hump as a single pet. There's no way to make it develop, especially if the fish is housed alone.
As for making him a wet pet, you could work at it by offering tempting foods such as frozen bloodworms or krill by hand. My con is indeed a wet pet who flares at me and follows me around the room as he watches me. This type of temperament may not develop until a male grows to adult size, because a single juvenile may be rather timid.