Translation

非社交的な / 人付き合いを好まない / 社会的交流が少ない

Meaning

Asocial describes someone who avoids or has little interest in social contact. It does not mean harmful or criminal toward society. The key trap is confusing asocial with antisocial, which often means hostile or disruptive.

Examples

• 彼は失礼なのではなく、ただ人付き合いをあまり好まないだけです。
  He is not rude; he is just asocial.
• 在宅勤務で彼女はさらに非社交的になりました。
  Working from home made her more asocial.