The leech is the classic image of something that drains you, so dream books read it as a tie, a habit or a demand that takes more than it gives.
Where in your waking life have you met something like this lately?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.