Sour is a laidback and gentle Felico who is somewhat naive about the world around him. He has a natural tendency to be friendly toward everyone he meets, sometimes to the point of being overly trusting. Sour is always willing to help out those in need, no matter how small or big their problem may seem. His levelheaded personality and kind demeanor make him very approachable, and everyone enjoys being around him. However, his trusting nature can sometimes make him vulnerable to being taken advantage of by others.

Ref:

https://www.deviantart.com/ev-zero/art/Sour-Cream-Info-977646725