Tick bites carry Lyme disease, tularemia, and a host of other scary diseases. They can even, in some instances, turn you into a vegetarian. Sometimes, though, a tick isn't scary because of the diseases it transmits when it bites you, but rather where it bites you. Your penis, for example.
Top image by John Tann via Flickr.
As the intrepid curators of weird science at the Annals of Improbable Research report, ticks on dicks aren't terribly uncommon. The tend to prefer the warm, damp environs of the groin and underarms. So in the early 1930s, when Hungarian physician Franz Gáspár met with a patient whose penis was harboring a tick the size of a hazelnut right around mid-shaft, he promptly removed it and regarded the whole situation as none-too-strange.
...but as the patient confessed he had regular (5-6 days interval) untroubled intercourse during two months with the swollen tick firmly attached to his member, he decided to publish:
“Gut entwickelter Holzbock am Glied – ungestörter Geslechtsverkehr [Well-developed tick on member – undisturbed intercourse]” in Acta Dermato-Venereologica 15 (1934): 523-524
Emphasis added. Because... oh, we're so happy your intercourse was "undisturbed"? But now we're disturbed. So thanks for that.
See pictures of the offending arachnid over at AIR, where you'll also find a link to a related YouTube video.