The answer is personality.
Character refers to the moral and ethical qualities of a person, such as honesty, integrity, and kindness. While character is an important aspect of a person, it does not fully encompass how they act, feel, and think.
Mood refers to temporary emotional states or feelings, such as happiness, sadness, or anger. Moods are transient and do not provide a comprehensive description of a person's consistent behavior and thoughts.
Temperament refers to the innate traits that influence how a person reacts to the world, such as their level of emotional reactivity or sociability. While temperament is a component of personality, it does not cover the full range of behaviors, feelings, and thoughts.
Personality is the combination of characteristics or qualities that form an individual's distinctive character. It includes consistent patterns of behavior, thoughts, and feelings. Describing how your best friends act, feel, and think aligns with describing their personality.