what about an american cocker spaniel? they are medium, don't shed to much (considering their longhair.) they are quite loyal and affectionate. if u live by yourself they will be a one person dog, but if there are more people they will pay attention to everyone.

also what about a bull terrier, from what i've experienced they are a one person dog, even with more then one person in the room they will warm up and pay attention to only one person. i don't think they shed to much and they are medium sized; unless you get the mini bull terrier they are alittle smaller.