Dogs! My Doberman would occasionally have a bulbous, or still lesser occupant. The vet told us to make sure to get the head out when ridding him of them and some alcohol or hydrogen peroxide might help. My thumb and fingers of my right hand have tough hard longer fingernails for playing guitar. I'd scrap across digging them out, like an occasional scratch gone wild as he relaxed. They were mostly very well entrenched. Fortunately they are not very prevalent here and a couple of tedious preventive tick baths each year took care of the problem. He loved the massage.
I have only experienced one infestation that I remember, as a boy in Virginia, we snuck onto a golf-course, wading near a pond, getting golf balls. These fresh attachments were scraped off with tweezers, taking care to be thorough.
The story of Jim Livingston crying helpless and scared, with one attached to the end of his penis in scouts was told around many a campfire for years afterwards. If we got together to camp again, the legend would probably still continue. His dad, the scout leader, took care of the problem while the pack watched and learned. I believe that he used tweezers.
Jbee