Loner
A loner is a person who does not seek out, or actively avoids, interaction with other people. There are many potential reasons for their solitude. Intentional reasons include introversion, mysticism, spirituality, religion, or personal considerations. Unintentional reasons involve being highly sensitive or shy. More than one type of loner exists, and those who meet the criteria for being called loners often actually enjoy social interactions with people but display a degree of introversion which leads them to seek out time alone.