A person who is single-minded and obsessive with regard to the study of theology.
Social ineptness does not automatically follow, but said person is as likely to want to talk about things other than theology as a CompSci is willing to talk about things other than computers. They often have preferences for dark churches, (as opposed to darkened rooms). Members of this species often display a marked preference for bread and wine, as against coffee. They will also have spotted the pun in the previous sentence. TheologyGeeks hang around Theology faculties and often sit at the front of lecture theatres, in order to guarantee receiving handouts.