The description matches the characteristics of Schizoid Personality Disorder.
People with this disorder often appear emotionally detached and show little interest in social relationships.
They prefer to be alone, are introspective, and may have a rich inner fantasy life.
They do not seek or enjoy close relationships and tend to appear cold or indifferent to praise or criticism.
Such traits differentiate schizoid personality disorder from other disorders like avoidant or schizotypal.
Therefore, Rahi’s behavior best fits the definition of schizoid personality disorder.