Fancy rats are an acquired taste in companion animals. Unlike a gerbil or hamster these rodents will go out of their way to interact with and please you. They have generally sweet dispositions and do not attack like hamsters more so than gerbils will. Degus are a close second in friendliness but lack the profound intelligence and need to please the hand that feeds them of the rat.
Finding common ground with family members is a valid consideration when you opt for a rodent pet. In general, mothers, wives, and paramours are adamately opposed to their presence in their households. They are less attuned to that "sweet" behavior indigenous to the rat species and as such are a hard sell in many homesteads. My Mom always referred to rodents as "the mouses" ... be they gerbils, hamsters, degus, or whatever.
Regardless, if you choose a rodent as a companion animal they will require cages and accommodations for hygiene, nutrition, hydration, and exercise beyond the typical water bowl and food dish of some canine or feline pet.
Today is Fancy Rat & Mouse Day. It is observed each November 12 annually. Do not confuse the common and dirty street rat for a fancy animal which is inherently clean and accommodating of the perceived wishes of their hosts.
My days of rodent ownership having long past, I still recall a time when they were a highlight of my day. After dealing with the rats who teach and administer college coming home to an honest predictable animal devoid of treachery was a refreshing change of pace for me personally.