What Bores through a hosts skin to its blood vessels then attaches with suckers to act as a parasite?

The organism that bores through a host's skin to access blood vessels and attaches with suckers to act as a parasite is typically a leech. Leeches are segmented worms that feed on the blood of various animals, including humans. They use their suckers to anchor themselves to the host while they feed, often secreting anticoagulants to prevent blood clotting during the process.