Rats are friendly but I have trouble getting past their hairless tails!
My preference would be a bird just because we used to have a budgie that was our buddy. My sister had a very friendly and loving cockatiel with a big vocabulary. Get one that is very young and hand fed, not a big box pet store bird. Handle it frequently. Depending on what you get you can teach it to talk, to do tricks. They are very social and will want to interact with you. My bird loved to have its head scratched. Be sure to read about specific birds before you get them, some have a pretty loud noise level and some are extremely long lived.
Trek Madone 4.7 WSD
Cannondale Quick4
1969 Schwinn Collegiate, original owner
Terry Classic
Richard Feynman: “The first principle is that you must not fool yourself and you are the easiest person to fool.”